A viral video shows former boxing champ Julius Francis knocking out a man outside Boxpark Wembley.

The video shared on Twitter shows the former British and Commonwealth heavyweight champion, now working as a bouncer, as the Boxpark security team intervene between two groups of men arguing outside the Wembley venue.

One man is heard repeatedly swearing to another man, shouting “f**k your family” and “I hope you have a heart attack”.

The man is then seen pushing a security guard and the Boxpark team attempts to separate the groups.

When escorted away, the first man is seen trying to push back to attack the others, until he walks towards Mr Francis.

In the video, Mr Francis strikes the man, knocking him out with just one punch.

Afterwards the man seems to be lying unresponsive as his friends attempt to put him into the recovery position.

While not confirmed, it is understood that the fight outside Boxpark took place on Monday (June 13).

Mr Francis, 57, once faced Mike Tyson in 2000 in Manchester.

Before retiring in 2006, he secured several belts and won 23 of his 48 fights.

Boxpark's CEO Roger Wade defended the bouncer, praising his character and community work.

He said: "He is one of the nicest people I have ever met and helps train young underprivileged kids boxing in his spare time.

A Boxpark spokesperson said: "Our team are aware of footage being shared online. This incident is currently under review and part of an ongoing investigation, and therefore we are unable to comment further on the incident at this time.

"We would like to stress that the safety and welfare of our customers and our staff is our number one priority."

Following the fight, police say they are now looking into the investigation.

The Met Police said: "Police are aware of footage circulating on social media showing an incident involving security staff and a member of the public outside Boxpark in Wembley.  

"An investigation into the circumstances, including to establish the identity and welfare of those involved, is under way.

"There have been no arrests and enquiries are ongoing."

Anyone with information is asked to contact police on 101 or tweet @MetCC and quote CAD1194/14June.

You can also provide information anonymously to the independent charity Crimestoppers on 0800 555 111.