Three asylum seekers are being flown to Fremantle Hospital after being badly injured in a mass brawl involving 150 Sri Lankan and Afghans at the Christmas Island detention centre.
Thirty-seven men were injured as detainees wielded broom handles, pool cues and tree branches as weapons during the violent fight last night.
"Obviously there's some reasonably serious injuries inflicted," an Immigration Department spokesman said.
Ten detainees were treated at Christmas Island hospital and some guards suffered minor injuries while breaking up the fight, the spokesman said.
It took detention centre staff about 30 minutes to stop the vicious brawl but once under control, there were no further incidents.
The spokesman said it was too early to say what triggered the violent confrontation, which started about 7.30pm.
"This was a confrontation between a group of (Afghan and Sri Lankan) detainees, it was not aimed at staff or the centre itself," he said.
There were 969 asylum seekers detained in the centre, which is designed for 1088 people.
The Immigration Department and Australian Federal Police are investigating.
Forty-four boats carrying 2133 passengers have entered Australian territorial waters this year.
