STRASBOURG, France (Reuters) - The UK Independence Party (UKIP), which played a key role in securing Britain's vote to leave the European Union, was at "breaking point" on Friday with the main contender to be its new leader in hospital after a scuffle with a colleague.
Steven Woolfe suffered seizures and needed brain scans after he collapsed following a "physical" confrontation at a heated meeting of UKIP's European Parliament members (MEPs) in Strasbourg to discuss the party's future.
"People have worked too long and too hard to get UKIP to where it is today, but it is clear that we ourselves, are at breaking point," said businessman Arron Banks, the populist party's most prominent donor.
The anti-EU UKIP, which is no stranger to infighting, has become a political force in Britain in recent years, riding on a surge of euroskepticism and concerns about immigration.
It has 22 MEPs, two more than either Prime Minister Theresa May's ruling Conservatives or the main Labour opposition, and took almost four million votes in the 2015 national election.
However, since it achieved its main goal helping force June's referendum and securing Brexit, its hopes of becoming the main opposition by winning over Labour supporters from its northern English heartlands where support for leaving the EU was strong have been severely dented by internal divisions.
Its well-known, charismatic leader Nigel Farage announced he would step down after the referendum but his elected successor Diane James quit this week after just 18 days saying she lacked sufficient authority.
Woolfe then angered some in his party when he said he would stand for the leadership but then also admitted he had considered defecting to the ruling Conservatives.
Matters came to a head at the meeting on MEPs on Thursday to discuss these comments leading to a clash between defense spokesman Mike Hookem, 62, and Woolfe, 49.
"The meeting was called to discuss the concerns over Steven Woolfe ... just what was happening and could we trust him as a leader, is he going to jump ship in the future," Hookem told the BBC.
Hookem denied he had thrown any punches, but said there had been a scuffle after Woolfe had approached to attack him. They had wrestled and Woolfe had fallen back but had got straight up.
"Steven has this morning reached out the hand of friendship to Mr Hookem, to Mike, and has realised that things did go too far in the MEP meeting," UKIP MEP Nathan Gill told reporters on Friday after visiting Woolfe who will be held in hospital's neurological department for another 48 hours as a precaution.
There will be no police action but UKIP will hold an internal investigation and the European Parliament is to launch a disciplinary inquiry.
Back in Britain, public recriminations amongst party figures came to the fore while newspaper front pages featured a picture of an unconscious Woolfe sprawled face down in the European parliament building.
"UKIP out for the count," said the Daily Mail's headline.
Neil Hamilton, UKIP's leader in the Welsh Assembly, said the police should have been involved, calling the incident "absolutely appalling".
Meanwhile party donor Banks denounced Hamilton on Twitter as "an odious toad", said he would no longer back UKIP if Hamilton and Douglas Carswell, UKIP's only representative in the Westminster parliament, remained in the party and Woolfe was not allowed to run for leader.
Despite the turmoil, senior figures in the party, which has in the past seen claims of racism, misogyny and homophobia against its members, believe it can shrug this off.
"As we've discovered many times with UKIP, we are a bit Teflon so things get thrown at us and it seems to bounce off," Gill said.
Additional reporting by Alastair MacDonald in Brussels; Writing by Michael Holden in London; Editing by Andrew Heavens