Nevada's secretary of state has expressed concern at the number of rejected ballots due to a mismatch in signatures in the counties of Clark and Washoe, US media reports.

The signature on a Nevada voter’s mail-in ballot envelope is matched with a signature in a voter database. Any mismatch in signatures needs to be "cured" - or verified - by the voter.

The New York Times reports that more than 11,300 ballots were identified by the state last night as still needing curing in Clark County, and more than 1,800 in Washoe County.

CNN reports that the secretary of state, Francisco Aguilar, has been texting voters who need to verify their signatures before their ballots can be counted.

Both outlets say there is a trend of young voters not having matching signatures.

The deadline for this process is 12 November.

Image source, Getty Images

Kari Lake, Republican nominee for the Senate in Arizona, says she will "accept the results of the election".

Speaking to the press, she says she has some "concerns" but work has been done to prevent problems.

Lake has long been a supporter of Donald Trump's unfounded claims that he lost the 2020 election unfairly.

She has also refused to accept the results of the 2022 midterms when she lost the race for governor to Democratic Katie Hobbs. Shortly after, she posted on X: "Arizonans know BS when they see it."

Chris Jeavans
Senior data journalist

We’ll be reporting on the exit poll results over the next few hours.

Unlike in the UK, the polls do not directly predict the result of the election, but builds up a picture of voter opinions and motivations, and a breakdown by age, gender, education and other demographics.

Pollsters Edison Research collect data on behalf of a consortium of news organisations by asking thousands of people across the country, including swing states, to fill in questionnaires as they leave polling places.

They supplement this with telephone surveys to capture the views of people who voted early, as almost 80 million Americans have.

The data starts to flow in from 17:00 US Eastern time (EST), 22:00 GMT, and gets updated.

Whenever you see an exit poll number, remember it’s a snapshot that could change and that there is a margin of error, so think of the numbers as a guide rather than a cast iron fact.

We've just heard from Capitol Police Chief J Thomas Manger, who spoke to the press in Washington DC about an arrest made at the Capitol visitor centre.

He says that at about 12:20 local time (17:20 GMT) a white male entered the south entrance of the Capitol visitor centre.

When the man put his jacket and backpack through for screening officers saw what appeared to be "something in the shape of a firearm" and "two bottles in the backpack", he says.

As the man was standing there, one of the officers noticed a "faint odour of gasoline", he said. The smell was "much stronger" on the backpack and it appeared a bottle containing a substance - which police believe was either gasoline or "some other accelerant" - was leaking.

The man was then detained and arrested, Manger said. Police found a flare gun, a lighter and a torch lighter, he added, and there were also "other articles" in his backpack.

The man had "papers with him" and told officers his intent was to deliver them to Congress, Manger said. Police are still trying to determine "where in fact he did come from" and what his intentions were.

The investigation is "ongoing" and the man is in custody, Manger said.

We'll be reporting all the biggest results as the night goes on on this page.

You might be wondering where those results come from, and how those calls are made.

The BBC has two trusted partners that provide results - Reuters news agency and our US news partner CBS.

When we bring you a result, we call it a "projection". That's because our partners analyse incoming results data, and when they are confident that one candidate has an unbeatable lead in a particular race, they project the winner.

That projection is not the official result - but it nearly always proves to be correct when all the votes are eventually counted. The final result comes when states certify the results – often days or weeks after election day.

• You can read more about that process here

Police in Maine say they are aware of "swatting calls at schools" throughout the state "and the country".

Swatting is the act of making a hoax call to the police with the intention of provoking an emergency response.

Many schools are being used to host polling stations today. Maine State Police says there is "no threat to the public".

As we reported earlier, the FBI has said non-credible "bomb threats" have been made in "several states" – the law enforcement agency says many appear to originate from Russian email domains.

It's unclear if the two statements are linked.

Voting has been extended by 90 minutes in Luzerne County, Pennsylvania, due to the late opening of polling stations, official say.

Voting at the polling location in Laflin Borough will now end at 21:30 local time (02:30 GMT).

Earlier, two voting precincts in Cobb County, Georgia were also granted permission to stay open late due to delays in opening times.

A reminder that polls close at different times across the US, with the first closing at 18:00 EST (23:00 GMT) tonight and the last at 01:00 EST (06:00 GMT) early on Wednesday morning.

• When will we know who has won the US election?

Angelica Casas
Reporting from Georgia

I'm in the battleground state of Georgia, where every single vote could matter in this election - Biden won the state with fewer than 12,000 votes in 2020.

Four years later, Georgia polls indicate that Donald Trump and Kamala Harris are similarly neck-and-neck.

Watch the video to hear from some of the Georgia voters I spoke to after they cast their ballots.

Christal Hayes
Reporting from Arizona

In the swing state of Arizona, there’s a steady stream of voters filing into South Mountain High School in Phoenix.

There’s a DJ booth set up out front with speakers blaring a constant stream of jams and beats.

Several voters I chatted with here tell me they were on the fence about voting and said they didn’t like either candidate for president.

“I honestly wasn’t going to even come,” Vianey Marquez, 27, tells me as she sticks her voting sticker to her top.

“I figured I should make my voice heard,” the mother of two daughters adds. “I don’t like the way Trump expresses himself, especially when it comes to women.”

Walking out of the voting centre, Krystle Colter tells me she didn't "want to vote for either of them".

She eventually decided to back Harris because of her efforts to protect lower-income families, single mothers and abortion rights.

“It’s hard because I don’t believe in abortion for the most part,” she explains to me. “But when someone has been raped or it’s incest, I just can’t imagine that. If I were in that situation it would be hard to be forced to have a child.”

We are preparing to hear from the Capitol Police in Washington DC about an arrest they made. They took a man who smelled of petrol and carried a flare gun at the buildng's visitor centre into custody.

There have been a couple of other arrests and law enforcement incidents across the US today related to suspected election issues.

Here's a break down of what else has happened so far:

• The FBI said it believes Russia is behind non-credible bomb threats in several states
• There were five non-credible hoax bomb threats in the state of Georgia
• Another two people were arrested in Michigan over making election-related threats
• In Maine, state police said they were aware of swatting calls throughout the state, but noted there was no threat to the public

We reported earlier that Kamala Harris has been participating in several radio interviews today - all of which have been in key swing states.

She's been encouraging Americans to "get out and vote" throughout the morning and lunch hour, most recently calling into Wisconsin (101.7 The Truth in Milwaukee), Nevada (KCEP with Lady AK in Las Vegas), and Radio Campesina Network (which is based in Phoenix, Arizona, but is also carried in Nevada, among other states).

Earlier she appeared on Atlanta station WVEE-FM, The Big Tigger Morning Show in Georgia, and Pittsburgh-based The Big K Morning Show with Larry Richert, where she shared her plans to have dinner with her family this evening before hosting her election night party at Howard University.

Over the last days and weeks both Kamala Harris and Donald Trump have been targeting voters in the seven swing states that will decide the election result.

Image source, Getty Images

Donald Trump will be joined by Tesla and SpaceX boss Elon Musk this evening, according to CBS, the BBC's US partner.

The former president's campaign is hosting a watch party at Trump's Mar-a-Lago home and Palm Beach Club for thousands of supporters.

It is not clear if Trump and Musk will attend these events, but a source close to Musk says the pair will be together.

Elsewhere, President Joe Biden and First Lady Jill will watch election results in the White House with long time aides and senior White House staff.

Bernd Debusmann Jr
Reporting from Philadelphia

We've just gotten word that another election-related legal complaint has been filed in Pennsylvania - this time in Luzerne County, which includes the town of Wilkes-Barre.

Court documents shared by the Pennsylvania Court system say that a polling location in Laflin Borough was delayed in opening by an hour and a half, "causing an inability for some voters to cast a ballot" if they had to leave by then.

In response, the court granted a petition to allow voting in Laflin Borough to continue through 21:30 local time - 90 minutes after polls have closed elsewhere in the state.

The Pennsylvania Court system has now confirmed that election cases have been filed in three counties :Luzerne, Northampton and Cambria.

State officials have, however, been quick to dispel any rumours of legal complaints being filed in other parts of Pennsylvania, and have been sending regular updates as the day goes on.

Brandon Drenon
Reporting from North Carolina

I bumped into local resident Arthur McCutcheon at a grocery store in Black Mountain, North Carolina, where National Guard trucks and troops are stationed in the parking lot to help Hurricane Helene victims.

“We voted this morning around 06:30,” McCutcheon says, adding that he voted for Trump as he did in 2016 and 2020.

McCutcheon says his issue is immigration. That's a key talking point that Trump has hammered since entering the political scene and one that is personal to this North Carolina voter.

He spent 15 years in Central America, he says, working with “prisoners and gang members” through a Christian missionary organisation.

“On the radio in Honduras, they advertise coming to the US, telling people they can get free benefits or get rich here,” he says. He recognizes that many migrants genuinely come to America looking to improve their lives but asks: “For every success story, there are how many failures?”

Bernd Debusmann Jr
US election reporter

Image source, EPA-EFE/REX/Shutterstock

The results of the election will not be official until votes are counted and verified, which could take days to fully complete in some instances.

In the battleground states, the process will be highly scrutinised. Trump is already questioning the trustworthiness of many of their voting processes, and he challenged the results of many of their votes in court in 2020.

Here is what to know about voting in 2024.

When does vote counting begin and how long will it take?

The first polls will begin closing at 18:00 EST (23:00 GMT) on Tuesday, but counting votes will extend far beyond then.

In most cases, it can take weeks to reach an official tally, partly because of state rules.

Who does the counting?

Counting, too, varies from location to location and depends on equipment used.

Some counties "feed" ballots into scanners, while others may use touch-screen systems or ballot-marking devices to record votes.

What can slow down the process?

The counting can be slowed down by disruptions, legal challenges or complications around provisional ballots.

Numerous legal challenges have already been filed.

When would a recount take place?

Each state has its own procedure for recounts and what can trigger them.

In the battleground states of Pennsylvania and Michigan, recounts automatically occur when the numbers of votes received by each candidate are especially close.

Read the full article by Bernd here

BBC’s Anna Foster reports from one of the US's biggest battleground states, Pennsylvania, explaining its crucial role in the outcome.

For presidential elections, many states vote for the same party, election after election.

That leaves just a handful of states - known as “swing states” - where either candidate could win.

Three of the seven swing states at this election are in an area known as the Rust Belt, the former heartland of the US manufacturing industry.

Pennsylvania, Michigan and Wisconsin share many similarities in their voter demographics and as a result have all voted the same way at every election since 1992.

Assuming the more predictable states vote as expected, Kamala Harris will find herself 44 electoral college votes short of the 270 she needs for victory and Donald Trump will be looking for 51 more votes to reach 270.

If that happens, the election could be decided in the Rust Belt alone.

• Read more about the swing states in our visual explainer on the Path to 270

The FBI says there have been "bomb threats" to polling stations in several states, and that many "appear to originate from Russian email domains".

"None of the threats have been determined to be credible thus far," it says.

We reported earlier on hoax bomb threats in Georgia, which Georgia Secretary of State Brad Raffensperger said were non-credible and of Russian origin.

The FBI says election integrity its highest priorities and that it is working closely with state and local law enforcement.

Image source, Getty Images

The US Capitol police says it has just arrested a man who "smelled like fuel" and had a "flare gun" at the Capitol visitor centre in Washington DC.

In a post on X, the police say the man was stopped during its screening process at the centre.

"The man smelled like fuel, had a torch and a flare gun," the post says.

The centre is closed for tours today while police investigate, the post adds.

The police force says it will provide more information when it can.

The US Capitol is where Congress, the legislative arm of the federal government, sits.

The Visual Journalism Team
BBC News

The winners of most presidential elections this century became clear pretty quickly - Obama’s 2008 and 2012 victories were both announced before midnight Eastern time on polling day, Donald Trump won by 03:00 Eastern time the next morning in 2016, and George W Bush’s re-election confirmed the day after the election in 2004.

But there are two notable exceptions.

It took nearly four days after polls closed on 3 November 2020 for US TV networks to declare Joe Biden the winner over Donald Trump, after the result in Pennsylvania became clear.

And in 2000 George W Bush and Al Gore’s campaigns went to war over a tight contest in Florida. The US Supreme Court voted to end the state’s recount process, which kept Bush in place as winner.

Gore conceded on 13 December - 36 days after the election.