Two teenagers have been arrested by police investigating the fatal stabbing of a man in London's West End.

Steven Bigby, 22, was stabbed in the chest soon after leaving a McDonald's restaurant on Oxford Street with friends on Monday afternoon.

Detectives arrested two men aged 18 and 19 in connection with the killing.

Police said Mr Bigby died after two groups clashed in a "spontaneous incident". A knife has been recovered from the scene.

A post-mortem examination showed the victim died from a single stab wound to the heart.

Rape trial

It has also been reported that Mr Bigby was awaiting trial for the rape of a 16-year-old girl and that, in a separate case, he was due to go on trial for wounding with intent and violent disorder.

Earlier, police revealed a row had broken out in McDonald's during which a drink was thrown.

Det Ch Insp Bob Mahoney said: "The incident escalated very quickly and Steven was fatally stabbed.

"At the moment we are treating it as a spontaneous incident. There is nothing to suggest that this is a gang-related crime or linked to any other incidents."

Mr Mahoney also appealed to witnesses who took photographs of the incident to come forward.

The teenagers arrested on Tuesday are being questioned at an east London police station.