Police said they arrested a man outside London's Paddington Station on Monday but added that the incident was not terrorism-related, a few hours after a van ploughed into worshippers near a mosque in the British capital.

"Officers have arrested a man outside Paddington for public disorder and possessing an offensive weapon. The incident is not terror related," British Transport Police said in a statement.

Video footage posted on Twitter showed officers restraining a shirtless man outside the station before taking him away.

Police have said the earlier attack at the mosque, which injured 10 people, appeared to be a terrorism-incident which would make it the fourth such attack in three months in Britain.