A man has been stabbed at an event which Jessie J had earlier performed at.

The BBC reports that police attended the London event - which was hosted by the makers of mobile phone BlackBerry - after a man was stabbed in the neck.

A spokesman for Scotland Yard said that a 25-year-old man has been arrested over the incident.

The victim, a man in his early 30s, is in a "serious condition" in hospital. It is thought he was stabbed with a broken bottle.

A spokesman meanwhile for BlackBerry makers Research In Motion said:

"Our first concern is the well-being of the individual concerned. We are doing all that we can to assist the police with their inquiries."