Riot at asylum seekers detention centre, Christmas Island

Tents used to house asylum seekers were razed, after Australian Federal Police (AFP) used tear gas to quell a group of about 250 protesters attempting to break out of the centre.

A small number of asylum seekers and staff suffered minor effects from tear gas and smoke, the immigration department says.

Two asylum seekers have been taken to hospital, one with chest injuries and another suffering chest pains unrelated to the incident that began about 8pm (local time) on Thursday.

Immigration department spokesman Sandi Logan said the group were "intent on violence and non-compliance".

"They (police) called on the group to stop and to return, they refused and at that point the AFP did what was required of them," he told Sky News, referring to the tear gas.

Christmas Island shire president Gordon Thomson said asylum seekers were being accommodated at a recreation centre, after two large tents were "burnt to the ground".

Foreign Minister Kevin Rudd told the Seven Network the protests were "completely unacceptable" and would not influence any visa decision.

Mr Logan said immigration staff had spent "considerable time" engaging with protesters over the past week.

Refugee advocates say the protest was sparked by a letter asylum seekers received from Canberra indicating security checks would be undertaken next month.

But Refugee Action Coalition spokesman Ian Rintoul believes it contained other information that led to the protests, and, along with the Australian Greens, he called for restraint.

"It is obvious the use of force by police is leading to escalating tension and confrontation," he said.

Human Rights Commissioner Catherine Branson is concerned about processing delays, urging detention as a last resort.

More than half of the 6500 asylum seekers in detention have been there for more than six months, she said.

"This causes stress levels to rise, it gives rise to problems in centres (including) mental health," she told ABC Television.

Opposition immigration spokesman Scott Morrison told Fairfax Radio the fire and protests were the direct result of Labor's soft border protection policies.