We're going to end our live coverage of the day's events, so here's a recap of what has happened:

• Ahmad Khan Rahami, a naturalised US citizen born in Afghanistan, is arrested on suspicion of being behind the New York and New Jersey blasts
• He is held in Linden, New Jersey after a shootout with police - two officers are injured and Mr Rahami is treated for a gunshot wound
• Officials say they are investigating whether he had been radicalised

• An explosion in Manhattan late on Saturday injured 29 people; another device was found nearby

• Early on Monday, a backpack containing up to five devices exploded in Elizabeth, New Jersey, when a bomb disposal robot tried to deactivate it

Flee Jones, 27, told the New York Times, external that Mr Rahami's appearance and behaviour began to change after he visited his native Afghanistan about four years ago. 

After returning home from his trip, he grew a beard, began wearing traditional Muslim robes and prayed in the back of the store. 

Image source, Reuters

Over the course of the day, the presidential candidates have taken several pot-shots at each other in response to the blasts - this time, it's Hillary Clinton's turn.

She had earlier said it was crucial to acknowledge that the vast majority of Muslims in America were peaceful - only for Mr Trump to speak out against "radical Islam", and for his adviser to emphasise how unsafe it was to let in refugees.

Speaking to reporters in New York state in the past few hours, Mrs Clinton said:

There's plenty we do know about the blasts and suspects Ahmad Khan Rahami.

So what don't we know?

• The motivation for the attacks: while investigators are now considering them as acts of terror, they said they are still looking into whether Mr Rahami had been radicalised
• Was there a link to the Islamic State group? While media linked to IS were quick to claim a link to the attack that injured nine in a Minnesota mall on Saturday, there has been no such claim in this case - at least not yet
• How authorities pinpointed the suspect: Some details have been revealed, and plenty of speculation has followed - whether a mobile phone used in one device was registered to Mr Rahami, for example - but a clear narrative has not yet emerged

Anthony Zurcher
BBC North America reporter

Hillary Clinton's remarks may have revealed a bit about how she views the current dynamics of the race. Twice she noted that she is the "only candidate in the race" who has made life-and-death decisions on engaging enemy combatants on the battlefield.

"I have sat at that table in the [White House] Situation Room," she said. "I've analysed the threats. I've contributed to actions that have neutralised our enemies. I know how to do this."

With those lines Mrs Clinton not only attempted to differentiate herself from Mr Trump, but also from third-party candidates like Libertarian Gary Johnson and Green Party candidate Jill Stein.

Recent polls show those two candidates cutting into, external Mrs Clinton's lead, particularly among young voters. Perhaps this is the beginning of an effort by the Democrat to use the national security issue as a way to prevent Americans from casting ballots for these lesser-known candidates.

Read more here

Image source, AP

Two homeless men discovered the backpack which contained five pipe bombs and saved hundreds of lives by reporting it to police, said Christian Bollwage, the mayor of Elizabeth, New Jersey.

The backpack was found near a rubbish bin at a train station. It exploded as a police robot tried to deactivate the explosives.

"They were walking with angels. They carried this [backpack] 800 to 1,000 yards before they dropped it," Mr Bollwage said. They had initially thought that the backpack contained valuables because they saw the wires inside.

He added that police are speculating that Ahmad Khan Rahami, who police have arrested in connection to the attacks, was trying to dump, external the backpack in order to conceal evidence.

Image source, AP

Ahmad Khan Rahami is the man officials say was suspected of being behind the New York and New Jersey blasts - but who is he?

Ryan McCann, a neighbour of Mr Rahami's in Elizabeth, New Jersey, said: "He's a very friendly guy, that's what's so scary."

Mr Rahami's family run a fried chicken shop in the town, and patrons said he appeared to have been taking over restaurant operations from his father.

You can read more here

The Department of Homeland Security has admitted they mistakenly granted US citizenship to at least 858 immigrants who come from "special interest countries", which present a national security concern or have high rates of immigration fraud.

Donald Trump's campaign was quick to pounce on the error and warned that Hillary Clinton's "open border" policy will imperil the US.

The DHS mistake occurred because fingerprint identification was lacking in the immigrants' paper files. The DHS does not use electronic filing systems.

At least three immigrants-turned-citizens were able to acquire aviation or transportation worker credentials, giving them access to marinas and airports. A fourth has become a law enforcement officer.

At least two are being investigated for links to terrorism, external, according to the Washington Times newspaper.

Authorities say Ahmad Khan Rahami, the main suspect in the blasts, is undergoing surgery after being shot in the leg.

Grace Park, a prosecutor in Union County in New Jersey, said Mr Rahami was injured in a shoot-out with police in Linden, NJ.

James Sarnicki, police captain in the town, said two officers were injured - one after being shot in his bulletproof vest, and another when he was grazed by a bullet shot by Mr Rahami into his car.

Robert Boyce, NYPD's chief of detectives, told a press conference that officers are keen to speak to two men spotted on cameras in New York on Saturday night.

The men were filmed picking up a bag on the street, and walking away with it, having removed an object from inside. The object turned out to be the second device, that did not explode. US media said the men were being seen as thieves, not suspects.

Mr Boyce said the men may have "inadvertently pulled a wire" and defused the explosive device, while being unaware they had done so.

He said images of the men may be distributed in the coming days.

At the same news conference, William Sweeney of the FBI (left in pic) said there is evidence that links Ahmad Khan Rahami to the bombs in New York and in New Jersey. 

But he was not on the FBI's radar and there was "no information yet" about whether Mr Rahami had been radicalised.

He also said there was no evidence that a terror cell was active.

"We have every reason to believe this was an act of terror," says New York Mayor Bill de Blasio at a news conference.

Hillary Clinton cast herself on Monday as the most qualified to combat terrorism in the US after a weekend of violent attacks in three states. 

Going after Republican rival Donald Trump, she argued that his anti-Muslim rhetoric is helping Islamic militants to recruit new fighters.

The Democratic presidential candidate touted her national security credentials at a hastily arranged news conference outside her campaign plane, accusing Republican Trump for using the incidents to make "some kind of demagogic point".

Image source, Reuters

The mayor of Linden, New Jersey, has confirmed two police officers were injured in the shoot-out when the suspect was arrested.

One was shot in his bulletproof vest and another officer who was sat in a car was hit by a bullet fragment.

"Thank God that he [the first officer] had his vest on," said Linden Mayor Derek Armstead. 

"And I think that was very helpful for him. I think that saved his life."

Image source, Getty Images

While the arrest was carried out in the New Jersey town of Linden, there is also a heavy police presence in the neighbouring area of Elizabeth, specifically at a fried chicken shop.

Suspect Ahmad Khan Rahami's family lived above the shop. According to Elizabeth mayor Christian Bollwage, the premises is owned by the suspect's father and some of his brothers have worked there. 

Mr Bollwage said Mr Rahami's father and two brothers sued the city after it passed an ordinance requiring the restaurant to close early because of complaints from neighbours about it being a late-night nuisance.

CNN are reporting that the suspect, Ahmad Khan Rahami, was spotted by a police officer while asleep in the vestibule of a bar in Linden, New Jersey. The officer recognised him from the alerts issued on Monday morning, leading to a shoot-out.

Anthony Zurcher
BBC North America reporter

Shortly after word spread of the explosion in New York City, Donald Trump told a rally in Colorado that a bomb had gone off. "It's a terrible thing what's going on in our world, what's going on in our country, but we are going to get tough and smart and vigilant, and we are going to end it," he said.

Then an interesting thing happened.

For the next 24 hours, the Republican nominee – who is quick to share his opinion on pretty much everything – went quiet. Aside from a tweet offering condolences and best wishes, external to the “families and victims” of the bombing, Mr Trump was silent.

That was a marked contrast to Mr Trump’s reaction to the Orlando shooting in June and could reflect an acknowledgement on the part of the Republican’s campaign that discretion in the face of a national crisis is a wise strategy. After Orlando, Mr Trump sent out a tweet saying he appreciated the “congratulations” for “being right on radical Islamic terrorism, external”. He followed that up with a call for President Barack Obama to resign and a fiery speech blaming the shooting on US immigration policy.

There was some thought that a national security crisis might help Mr Trump in the general election, given that the Paris shootings in December boosted his Republican primary poll numbers. Surveys after Orlando, however, showed this was not the case. A Washington Post poll in late June, external gave Mrs Clinton a 50% to 39% edge in handling terrorism – an 8% improvement from May.

When asked which candidate reacted better to the shooting, 46% said Mrs Clinton, while only 28% opted for Mr Trump.

As the Post noted, it was one of the few times in the past 12 years where a Democrat scored better on “handling terrorism” than the Republican opponent.

Mr Trump has steadily chipped away at Mrs Clinton’s lead in the polls over the past few weeks after the Democrat surged ahead following the national conventions in late July.

The New York and New Jersey bombings represent a challenge for both candidates – and an opportunity to prove their mettle as commander-in-chief. If the Trump campaign has decided that a measured response is the best strategy, the real question will be whether the candidate can stick to it. On Sunday night, he was back on Twitter, launching a flurry of attacks, external against Mr Obama and Mrs Clinton.

On Monday morning he boasted during a telephone interview that he accurately described the explosions in New York City as a bombing before anyone else.“I should be a newscaster because I called it before the news,” Mr Trump said. “What I said was exactly correct.”

He also said his plan as president was to “knock the hell” out of the so-called Islamic State, stop being “gentle” and have law enforcement engage in profiling to prevent militant attacks.

Mr Trump has a rally scheduled this afternoon in Florida. Will the restrained Trump re-emerge - or was that a one-day phenomenon?