Spears' dancers fired for drug use

Britney Spears' world tour has been thrown into turmoil after three of her dancers were fired for failing drugs tests.

The 'Toxic' star kicked off her 'Circus' world tour in New Orleans, Louisiana on Tuesday night.

The concert features a group of dancers alongside Spears - but now three have been axed from the gigs after the drugs discovery.

A source tells RadarOnline.com: "I think (the fired dancers) just didn't expect to actually get tested. And drugs are just not okay so they had to go."

Spears' 'Circus' tour will take in more than 40 dates and conclude in London on June 14.