JET frontman Nic Cester collapsed on stage last night (10.08.09).

The Australian rocker was half-way through a concert at London's Hard Rock Café when he suddenly fell to the ground.

He quickly stood up, joking he had swine flu before fainting again.

The band's manager helped Nic off stage, leaving his bandmates Chris Cester, Cameron Muncey and Mark Wilson to struggle through three more songs without him.

Nic was rushed to University College Hospital in Euston, where he was treated for symptoms of gastroenteritis, acute vomiting and dehydration and held overnight for monitoring.

The band later revealed the singer had been feeling unwell all day, but insisted on performing so he wouldn't let any fans down.

JET's third studio album 'Shaka Rock' is due for release in Britain next month.

It includes a cover of Johnny O'Keefe's hit single 'Wild One', which the band recorded with punk legend Iggy Pop.