UKIP's defence spokesman accused the politician he punched of 'faking' his collapse
Both give differing accounts of the story. Woolfe told the Daily Mail that Hookem was "angry" following a tense meeting in which Woolfe admitted he had been considering defecting to the Conservative party.
He said that Hookem "came at me and landed a blow."
Hookem insisted that his colleague's version of events was "a total fabrication."
Woolfe suffered a seizure two hours following the pair's argument but Hookem told the Daily Mail that the incident had been staged.
"Now I'm not a medical man, but that was pure Hollywood to me the way he was face down," he said.
"I was expecting a police squad to come and draw a line around him. People I have met who have had seizures they do not go down like that. It's very suspect."
Hookem also posted a bizarre photo of his hands on his Twitter account in a bid to prove that he did not hit his colleague:
The MEP has also threatened legal action against Woolfe, who is favourite to be elected as the new UKIP leader following Diane James' resignation from the post after just 18 days.
'"I've got to get legal advice on my position if he carries on like this, stating that I punched him when it's a total fabrication and a pack of lies," Hookem said. "I'm taking advice on what is the next step to stop this man. I don't think he can salvage his leadership bid. This whole thing has shown him to be a liar."