Asylum seekers have rioted at an Australian detention centre in Sydney and set on fire many buildings.

Some of the detainees at Villawood centre also got onto the roof to unfurl banners and attacked firefighters and guards.

Rights groups said the long delays in the immigration applications process might have precipitated the violence.

But politicians condemned the actions as the "criminal behaviour" of people "not welcome" in Australia.

Al Jazeera's Andrew Thomas reports from Sydney.
About 100 detainees were involved in the protest at Sydney's Villawood centre.

Buildings were set alight and some detainees got onto the roof to unfurl banners and attack firefighters and guards.

Refugee groups say the time it takes to process applications is behind the violence

But politicians condemned the actions as the "criminal behaviour" of people "not welcome" in Australia.