Nigel Farage's top aide has lost his job in Ukip, as the party's leader battled to fight off an apparent coup against him.
Raheem Kassam, Farage's chief of staff, has had to watch from New York as the party descended into open warfare.
A damaging and volatile internal party split spilled out into the open on Thursday, after one of its senior MEP's launched a brutal attack on Farage's "snarling" style. One of Ukip's biggest financial backers, Stewart Wheeler, has called for Farage to step down.
Ukip's only MP, Douglas Carswell, has also been engaged in his own fight with Farage and Ukip officials over whether he should accept hundreds of thousands of taxpayer's money to spend on Commons staff - something the MP does not want to do.
Farage allies, including the party's deputy leader Paul Nuttall and donor Aaron Banks, have moved to lend support to the embattled leader.
Earlier this week Farage decided to U-turn on his promise to quit as leader should he fail to win election to the Commons as MP for South Thanet. The move surprised Carswell, who learned of the decision from Twitter.
Kassam appears to have been one of the first casualties of the battle. A party spokesman said: "Raheem Kassam no longer works for Ukip."
I was GE2015 staff. My contract has always expired at the end of the month and I am on holiday until then. Nigel is the best leader for UKIP— Raheem Kassam (@RaheemKassam) May 14, 2015
In other news, chill out guys. It's only a job, and one I enjoyed greatly.— Raheem Kassam (@RaheemKassam) May 14, 2015
UKIP's Patrick O'Flynn says Nigel Farage "is my political hero" as he clarifies newspaper comments http://t.co/ywaONdv7h8— Sky News (@SkyNews) May 14, 2015
In an extraordinary Times interview, O'Flynn claimed Farage had become a "snarling, thin-skinned, aggressive" man whose behaviour risked the party looking like an "absolutist monarchy". And today he hit out at "poisonous individuals" close to Farage who want to push a "hard-right, ultra-aggressive American Tea Party" approach.
One of O'Flynn's targets is widely assumed to be Kassam, who tweeted this morning: "What a lovely start to my holiday!" A former colleague of Kassam's told HuffPost sarcastically of his fall that it "couldn't have happened to a nicer person".
Wheeler, a former party treasurer who donated almost £100,000 to help fund Ukip's general election campaign, told BBC Radio 5 Live that Farage should go. He said: "I would like him to step down, at least for the moment. And if he wants to put himself up in an election, then he has every right to do so, though I personally would prefer somebody else now."
On Thursday afternoon, Nuttall said in a statement of support for Farage: "The general election was a great success delivering 4 million votes in the bag. The 2020 vision is on course. UKIP have the best communicator in British politics leading this party and who will play a vital role during the referendum campaign."
Nigel Farage is the greatest man this country has produced since Churchill Enough said UKIP— David Coburn MEP (@DavidCoburnUKip) May 14, 2015
Ukip MEP David Coburn said: "Nigel Farage is the greatest man this country has produced since Churchill, enough said."
And Banks, the party donor who has given £1m to Ukip, has said O'Flynn, Carswell and deputy party chairman Suzanne Evans should be thrown out of the party for appearing to challenge Farage.
Farage was reinstated as leader just three days after quitting, when the party's national executive committee (NEC) rejected his resignation. Farage, speaking to reporters outside the party's London office, said: "If the NEC unanimously back me, that's not my fault, is it?" As he left the building, he added: "I don't feel terribly aggressive, I have to say."
Ukip director Steve Stanbury told the BBC "I wouldn't really call it a civil war" at the heart of Ukip but there was a "robust conversation going on. What we need to do is look at the four million people who voted for us, our 50,000 members, and they expect something better and different from this."