Francesca Gillett
BBC News, Washington DC

So we had a bit of a wait for the vote, but when it came it all happened very fast. And it was very close.

House Republicans were hoping for a simple majority to pass their motion to impeach Alejandro Mayorkas, who as homeland security secretary is Joe Biden's immigration chief.

But four Republicans sided with the Democrats, which meant their majority wasn't there and so the impeachment effort failed.

As our correspondent writes, it's embarrassing for the House Republicans, but this may only be their first such attempt. Although they'd need a more solid majority in the House for it to succeed next time.

And it's obviously good news for Mayorkas, who has narrowly survived what the Democrats called a "politically motivated" impeachment attempt.

To read the full story about tonight's events, head here. For now, that's it from us.

The impeachment proceedings were started by hard-line Republican Marjorie Taylor Greene, and as you might expect, she's not happy with the result.

She's just told reporters on the Capitol steps that she'll try again.

“My colleagues who voted no, I think they’ll be hearing from their constituents," Greene says.

Anthony Zurcher
BBC North America correspondent

The Republican failure to impeach Homeland Security Secretary Alejandro Mayorkas has once again demonstrated the limits of the historically slim Republican majority in the House of Representatives.

The votes of just three Republicans were enough to sink the impeachment effort (with a fourth Republican switching at the last minute, probably for procedural reasons).

Instead of what was hoped to be a show of conservative dissatisfaction with Joe Biden’s immigration policies, the effort ends up as yet another embarrassing display of conservative lack of cohesion.

The Republican holdouts had objected to the precedent the impeachment move would have set – ousting an administration official not for official misconduct, but rather for policy objections.

That perceived bullet may have been dodged for the moment, but given the current acrimony in Congress, this may only be the first such attempt.

It’s clear, however, that the Republicans are going to need a more durable majority in the House if they want to succeed in their next go. And given this very public failure, conservative hopes of someday impeaching Biden have taken a serious blow, as well.

Image source, EPA

Immediately after the impeachment vote, another Republican bill was voted down.

It would have provided $17.6bn in military aid to Israel.

It was an attempt by House Republicans to pass their own standalone legislation, following a bipartisan Senate bill was put forward which included aid for Ukraine and border security measures.

By any account, it's not been a good night for House Republicans.

Democrats had full attendance on their side tonight, with Texas Representative Al Green even showing up in a wheelchair at the last minute to vote.

Republicans were missing one person because lawmaker Steve Scalise is out receiving cancer treatment.

Scalise is supposed to be back tomorrow, so if there was the same vote again with him included, the impeachment would pass. So there is a chance the Republicans could bring it up again.

In the end, four Republicans voted against impeaching Mayorkas.

Republicans Mike Gallagher of Wisconsin, Ken Buck of Colorado, House Republican Vice Chair Blake Moore and Tom McClintock of California were the nay votes.

Buck previously said that Mayorkas was "terrible, the border is a disaster" - but "that's not impeachable".

At the last moment one Republican switched their vote - from supporting impeachment, to against it.

It won't affect the outcome - a tie would have also sunk the effort - but it's a more definitive loss for the pro-impeachment side.

The impeachment motion looks like it has failed.

Lawmakers so far voted 215 to 215, meaning it was a tie.

A simple majority is needed for the motion to pass.

Three Republicans have voted against the motion.

The voting has just begun. Members have five minutes to submit their votes electronically.

Stick with us for updates - and you can watch along by pressing play above.

The vote in the House of Representatives has been delayed. While we wait, here's a reminder about what this is all about.

What is Mayorkas accused of?

The Republicans accuse Homeland Security Secretary Alejandro Mayorkas of "willful and systemic refusal to comply with the law" and "breach of public trust" over his handling of the migrant crisis at the US's border with Mexico.

They accuse him of failing to enforce immigration policies, allowing for a record number of illegal border crossings in recent months. And they also claim he lied about whether the border was secure, when he testified to lawmakers that his department had "operational control" of the border.

How did Mayorkas respond?

In a seven-page letter, he said "false accusations do not rattle me" and called them "politically motivated".

"The problems with our broken and outdated immigration system are not new," he wrote. "Our immigration laws were simply not built for 21st century migration patterns."

Mayorkas also wrote that his parents came to the US from Cuba, which instilled in him a "reverence for law enforcement".

What has Biden said?

In a statement on Monday, the Biden administration said it was "an unprecedented and unconstitutional act of political retribution that would do nothing to solve the challenges our nation faces in securing the border".

Image source, Library of Congress

It’s been a while – a long while - since Congress has been in this situation.

The last cabinet official to be impeached was William Belknap in 1876.

According to the US Senate website, Belknap was a former Iowa state legislator and Civil War general before becoming war secretary under President Ulysses Grant.

Grant’s administration was riddled with corruption and rumours began to fly about his war secretary, who led a lavish lifestyle on a relatively constricted government income.

Evidence suggested Belknap had taken bribes in exchange for lucrative trading contracts, and the House moved to impeach him.

He raced to the White House and handed in his resignation – but that didn’t stop the vote. The articles of impeachment passed, although the Senate failed to reach a two-thirds majority vote and did not convict.

Belknap avoided further prosecution over corruption allegations and died of a heart attack in 1890.

For Republicans, impeachment is just half the battle. If their measure succeeds and he's impeached, Alejandro Mayorkas faces a trial in the Senate.

The procedure is set down by the US Constitution - the House does the impeaching and then the Senate does the trial. Two-thirds of Senators need to agree in order to remove the secretary from office.

The trouble for Republicans is that the Democrats and their allies hold a 51-49 majority in the Senate chamber.

This whole battle has been split overwhelmingly along party lines, and it's difficult to see any Democratic senators breaking ranks.

So even if House impeachment passes today, it's highly unlikely that Mayorkas will lose his job after the matter goes to the Senate.

Earlier, US House Speaker Mike Johnson said he believed Republicans have enough votes to impeach Mayorkas and they planned to move ahead with the vote.

We'll know soon if he's right.

Last November, a group of eight Republicans voted to effectively stall the impeachment proceedings against Mayorkas.

But ahead of tonight's vote, only two Republicans have said they will vote not to impeach him.

The debate and vote is expected to start any moment. Stick with us for live updates or watch along by pressing play at the top of this page.

Image source, Getty Images

Voting will be under way in the House shortly, scheduled to start at around 17:30 EST (22:30 GMT).

The motion must pass by a simple majority to advance to the Senate, where Mayorkas would almost certainly be acquitted.

Republican House lawmakers have claimed they have the numbers to impeach Mayorkas. But that remains to be seen, as they hold slim control over the House - and Democrats are solidly against the motion.

Two Republican lawmakers have already said they will vote against impeachment. Four 'no' votes (assuming everyone shows up) and it fails.

Earlier, Republican Representative Tom McClintock of California said he opposes impeaching Mayorkas. Representative Ken Buck, a Colorado Republican, also said that "there's no impeachable offense".

The Republicans need a simple majority for the motion to pass. If it does, Mayorkas would be the second cabinet member in history to be impeached.

But he would almost definitely be acquitted in the Democratic-led Senate, where a two-thirds majority would be needed to convict and remove him from office.

Image source, Getty Images

Alejandro Mayorkas, a Cuban-born attorney, has served as the homeland security secretary since President Joe Biden named him in 2021.

He served in the department under the Obama administration and has also worked in private practice.

As the crisis at the border has escalated, Mayorkas has proven an unpopular figure among Republican lawmakers. They have accused him of breaching public trust and "refusing to comply" with immigration laws.

More specifically, they claim he violated public trust by telling Congress the border was "secure" and that the department had control over the border, which they claim is false.

They also argue he allowed a surge of migrants to cross the border by stopping several Trump-era immigration policies.

Mayorkas has hit back at the claims, saying the "false accusations do not rattle me".

Francesca Gillett
Live reporter, Washington DC

It's coming up to 17:00 here in Washington DC, where we're gearing up for a key vote later in the US House of Representative - which is the lower chamber of Congress.

Lawmakers are voting on whether to impeach Homeland Security Secretary Alejandro Mayorkas.

If they vote to impeach him, Mayorkas will become only the second cabinet member ever in US history to be impeached - and the first in 148 years.

So why's it happening? Well, it's over a policy dispute. Republicans accuse Mayorkas - who is Joe Biden's top border official - of being intentionally lax in securing the US border with Mexico. Mayorkas has denied any wrongdoing and has defended his tenure.

Democrats say Republicans are using the impeachment push to score political points ahead of the 2024 election. They and legal experts also say it fails to meet the bar of a "high crime or misdemeanour" for impeachment.

Remember, the border is a key election issue. More than 6.3 million migrants are recorded to have crossed into the US illegally since 2021, a record high.