A man accused of gunning down a father-of-four for disrespecting him in a McDonald's queue told jurors the victim shot himself.

Horace Campbell is said to have murdered Devon Scarlett, 34, after chasing him into a dead end on an estate in Brixton.

Mr Scarlett, from Thornton Heath, who was also known as Raymond Mitchell, was beaten and suffered bullet wounds to the thigh and stomach. He bled to death from an injury to his femoral artery.

Mr Campbell is alleged to have phoned Liam O'Callaghan, 18, to bring a gun to the scene after a petty argument in McDonalds with Mr Scarlett at about 6am on April 17, last year.

Giving evidence at the Old Bailey, the 27-year-old claimed it was Mr Scarlett who pulled the gun out after calling him into Marcus Garvey Way.

Mr Campbell of Tovil Close, Anerley, told the jury: "He said to me 'There's no cameras here now, what are you saying?', I said 'I don't want no trouble'."

He told the court he ran away up the road when he noticed Mr Scarlett had a gun in his hand.

He added: "He's come running after me and I've said 'Don't shoot, don't shoot'.

"He whacked me with something on the head, he made contact a few times. I have got up and started punching Mr Scarlett in his head.

"The gun is going off, he's trying to shoot us. It went off four times. He had the gun so the last thing I was thinking is that 'he's got shot'. As soon as he's dropped, I have kicked the gun out of his hand."

Mr Campbell admitted he may have punched Mr Scarlett as he lay injured and told him "you're not so hot now".

The court heard he grabbed the gun and ran out the garden while Mr O'Callaghan, of William House, Tulse Hill, picked up the ammo clip.

The jury were told Mr Campbell and Mr Scarlett had clashed after intervening in another group's argument.

Mr Campbell, who did not know the victim, said he only got involved to act as a peacemaker and told Mr Scarlett he was "blowing it out of proportion".

The prosecution claims Mr Campbell shot Mr Scarlett to avenge a "perceived lack of respect".

Mr Campbell and Mr O'Callaghan both deny murder.

The trial continues.