Ex-heavyweight boxer Julius Francis KOs troublemaker in scary incident

Police in the U.K. are investigating after a former heavyweight boxing star working secruity at Wembley Stadium was shown on video mercilessly knocking out a troublemaker.

Footage posted to social media on Tuesday shows Julius Francis, former British champion who faced Mike Tyson in 2000, deliver a fightening blow to a man who had been pushing and shoving with other staff members for several minutes.

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It is unclear what caused the fracas in the first place, with the man in questions wearing a blue durag and seen in the video cursing out staff at Wembley.

After the man was eventually shepherded away from the doors of the stadium he encountered Francis, briefly getting in his face before the 57-year-old former heavyweight hit him hard with a brutal short.

The punch crumpled the man instantly, with footage showing Francis walking away and the man's companions fearing for his safety.

Metropolitan Police confirmed they were investigating the incident, saying they were still trying to identify the man involved.

“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,” they said via statement.

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

“There have been no arrests and inquiries are ongoing.”

Former British heavyweight punches out Wembley troublemarker

BoxPark founder and CEO Roger Wade, who employs Francis, stood by his security guard in a post shared on LinkedIn.

Wade vouched for Francis' work with underprivileged youth as a boxing trainer, and gave more details about the other man's alleged conduct before he was thrown out and eventually punched.

"My understanding is that Julius and our security team spent 15 minutes stopping this man and his friends from abusing, spitting on and hitting our customers and staff," he wrote.

"They carefully escorted him from the premises under constant provcation and violence.

"Finally the person approached Julius in a confrontational manner and he defended himself.

"Acts of violence or abuse towards staff should never be tolerated.

"How would you react if someone approached you violently? What would you do next if you were in my shoes?"

Wade ended the meesage by hashtagging 'I stand with Julius'.

The video of Francis' shot on the man attracted more than six million views after it was posted on Tuesday afternoon.

Francis memorably faced Tyson in a one-sided bout back in 2000, in which the boxing legend ended the fight in the second round by TKO.

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