David Cameron describes Chelsea metro incident as "extremely disturbing"

British prime minister David Cameron has described the racist incident involving Chelsea supporters in Paris as "extremely disturbing and very worrying".

A video emerged showing Blues supporters on a metro in Paris persistently pushing a black person off the train and chanting "We're racist, we're racist, we're racist, and that's the way we like it".

Chelsea have vowed to ban any supporter found guilty for life and Cameron was asked to comment on the incident earlier today.

"It's obviously potentially a criminal offence and so I'm sure the French police will be looking at it very seriously," he told LBC Radio.

"I know the British police will give every assistance that they can. I'm sure Chelsea will co-operate with that fully. These are very, very serious matters."

Anyone found guilty of racial abuse by the authorities faces a possible three-year jail sentence and €45,000 (£33,160) fine.