The family of a “gentle giant” who was shot in the face after he asked three men in a nightclub to stub out their cigarettes because of the smoking ban was clinging last night to the hope that the boxing champion would survive the attack.

James Oyebola, 46, a former British heavyweight champion, was on a life-support machine in hospital. He had politely asked the men to stop smoking at the Chateau 6 club in Fulham, West London, shortly before 1am on Monday. One of the men produced a handgun and fired four shots, hitting Mr Oyebola in the face and leg at point-blank range.

Mr Oyebola, from Neasden, northwest London, was due to be honoured on Friday by President Kufuor of Ghana for his work for African boxing. The shooting is the first reported example of violence linked to the smoking ban since it was introduced in all enclosed public places and work-places in England on July 1.

A Scotland Yard spokeswoman said: “The shooting occurred after a discussion about the smoking ban. It occurred in the garden of the club.”

Last night, as the British Boxing Board of Control paid tribute to him as “one of nature’s gentlemen”, Mr Oyebola’s family said that they had received an “unprecedented show of support”.

Scott Ewing, a solicitor speaking on behalf of the family, said that Mr Oyebola was in a “critical condition” in Charing Cross Hospital’s high dependency unit. “Until the highly experienced doctors treating James decide to reduce the level of sedation it is not possible to ascertain the level of damage or prognosis.”

Mr Oyebola, who was known in the ring as Big Bad James, had finished work at a nearby bar and stopped off at the club in Fulham Road at about 11pm to join the owner for a drink.

A witness said: “Three young guys were smoking in the club and James asked them to put out their cigarettes. He wasn’t aggressive. He pointed out that smoking was against the law. But the three saw it as a sign of disrespect. On their way out one pulled out a gun and began firing at James.”

The shooting is being investigated by detectives from Scotland Yard’s Operation Trident unit, which investigates gun crime involving young black men.

Detective Chief Inspector Scott Wilson said: “It is a horrible crime to happen anywhere, but over nothing – an incident such as smoking – these people need to be caught. The altercation takes place, someone pulled out a gun and shots are fired. I can imagine it was over in 20 seconds.”

Police believe that the black suspects, aged between 19 and 25, ran from the club in separate directions. There were at least 40 customers in the nightclub, many of whom apparently panicked and ran away.

Mr Oyebola’s partner, Malin Bergstrom, and their two teenage children were believed to be with him at Charing Cross Hospital.

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