Celebrating her 20th birthday at A-list haunt Movida, the pop princess and her guests were ordered to evacuate the premises when a man threatened to blow himself up in London's West End.
Singer Jamelia's 30th bash in the same club was also ruined, and rapper Chipmunk's night out came to an early end.
'Thanks to (my friends) Movida and all my amazing rebels for the best Party...It was The BOMB (Pun Intended). Love you all,' Jamelia Tweeted after the drama.
The Regent Street stand-off between police and a 46-year-old man lasted until 5.15am, when he left the Accessorize shop in which he'd barricaded himself.
The man was being questioned by police yesterday.