4 April 2012 Last updated at 09:54 ET

Jessie J Blackberry event stabbing: Man in hospital

Singer Jessie J had earlier performed at the event

A man is in a serious condition in hospital after being stabbed in the neck at an event attended by singer Jessie J.

Police were called to the event hosted by smartphone brand Blackberry at Bankside Vaults nightclub in Southwark, central London, shortly after midnight.

A Scotland Yard spokesman said the victim, aged 37, was being treated at an east London hospital.

The spokesman said a 25-year-old man had been arrested and was in custody.

Police said it appeared the man had been stabbed with a broken bottle.

Jessie J had earlier performed at the event to promote Blackberry's instant messaging service.

A spokesman for Blackberry-maker Research in Motion (RIM) 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."

Jessie J is a judge on the BBC talent contest The Voice and has had two number ones.

She sent a message on Twitter which read: "My thoughts are with the person who was seriously injured last night at the BlackBerry BBM party. So sad. I really hope they are OK."