The party’s interim leader Nigel Farage issued a statement saying Mr Woolfe’s condition was “serious”, and subsequent reports have said his injuries may be “life threatening”.
It has been reported that Mr Woolfe collapsed outside the European Parliament after he was “punched by a colleague” during a meeting in which the party was aiming to “clear the air” amid a leadership crisis.
Why is Steven Woolfe seen as a Ukip leadership favourite?
In an astonishing week for Ukip, the party’s elected leader Diane James announced her departure after 18 days in the job.
She had taken over from Nigel Farage who has returned as interim leader.
On Wednesday, Mr Woolfe announced he would stand as Ukip leader.
Who is Steven Woolfe?
Mr Woolfe, who is a Ukip MEP for North West England, is a barrister and spent his early career working as a lawyer in the City of London. He subsequently spent several years as a hedge fund general council before entering politics.
He was appointed as Ukip’s economics spokesman shortly after Nigel Farage became leader of the party in 2010.
The pair are close and Mr Farage had signalled support for Mr Woolfe’s current leadership bid.
Mr Woolfe was elected to the European Parliament in 2014, and following Mr Farage’s resignation after the Brexit vote this year, was seen as a strong contender to lead the party.
At the time he said he would “ruthlessly” target Labour seats in the North and Midlands.
In August, ahead of the leadership election, it was revealed Mr Woolfe had failed to declare a drink-driving conviction when he stood for a police and crime commissioner post, in 2012, which is a criminal offence.
Why was he not on the leadership ballot after Nigel Farage resigned?
Despite strong party support after Mr Farage’s last resignation, the party’s national executive committee disqualified his application due to late submission.
It is thought Mr Woolfe’s application arrived just 17 minutes past the deadline.
Was Steven Woolfe considering a defection?
After Ms James was elected leader, reports of the possibility of Mr Woolfe defecting to the Conservative Party emerged.
One Ukip source told the Guardian he had considered it “very, very seriously.”
But Mr Woolfe addressed the rumours on Wednesday, issuing a statement which read: “I have been enthused by the start to Theresa May’s premiership,” he said. “Her support of new grammar schools, her words on social mobility and the growing evidence that she is committed to a clean Brexit prompted me, as it did many of my friends and colleagues, to wonder whether our future was within her new Conservative party.
“However, having watched the prime minister’s speech on Sunday, I came to the conclusion that only a strong Ukip can guarantee Brexit is delivered in full, and only our party can stand up for the communities of the Midlands and the north.”
In a statement, Mr Farage said: “I deeply regret that following an altercation that took place at a meeting of UKIP MEPs this morning that Steven Woolfe subsequently collapsed and was taken to hospital. His condition is serious.”Reuse content