Asylum seekers involved in a wild brawl on Christmas Island over the weekend are being threatened with deportation.

More than 40 detainees and five security staff were injured in the clash.

Prime Minister Kevin Rudd says detainees found guilty of serious offences as a result of the riot will have that taken into account during the processing of their asylum claims.

Mr Rudd and his Immigration Minister Chris Evans were peppered with questions during Question Time this afternoon about the riot and the Government's asylum seeker policies.

One-hundred-and-fifty people were involved in the half-hour brawl at the Christmas Island detention centre on Saturday night. Three detainees suffered serious injuries and were flown to Perth for specialised care.

It is claimed that pool cues, tree branches and broom handles were used in the fight between Sri Lankan and Afghan detainees.

Refugee campaigners say overcrowding led to the violence, but the Government says tension had been building at the centre for some time, due partly to concerns from some Sri Lankans that their asylum applications will fail.

Mr Rudd says the riot could affect the refugee applications of the asylum seekers involved.

"If a detainee on Christmas Island has committed a serious offence, this will be taken into consideration as part of the assessment as to whether or not they are granted a visa," Mr Rudd said.

Senator Evans says the Immigration Department is investigating the riot and Federal Police are looking at laying criminal charges.

"Those that were responsible, if we can identify them, will be prosecuted after an AFP investigation," he said.

"Clearly though security at the centre will be tightened to ensure we don't have any incidents like this again."

Capacity concerns

The Federal Government recently announced plans to expand the capacity of the Christmas Island detention centre to 1,400, but it is not there yet.

It can only accommodate 1,028 and the latest head count is 975.

Ian Rintoul from the Refugee Action Coalition has been in contact with some of the detainees since the riot.

He says many asylum seekers are worried by some recent deportations, but the sheer number of asylum seekers at the centre is the main reason for the riot.

"I have spoken to one Afghan and one Tamil detainee inside the detention centre. The incident seems like it was confined to just one compound, but they were aware of the situation and had spoken to people and the Afghan guy had observed some of it certainly," he said.

"What they say is that there was no particular cause. That is was a result, people are angry, people are frustrated.

"The overcrowded conditions inside simply boiled over inside the Green 1 compound and the Afghan detainee told me he was surprised it hasn't happened before and he is very certain that it will happen again."

Mr Rintoul says the overcrowding is leading to restricted access to recreation facilities and the internet has been cut off.

"There is restricted news access, restrictions on some of the access to kitchen facilities and making tea and coffee during the day, trying to save," he said.

"It is those kinds of tensions or there are ethnic tensions simply to divert attention away from the deteriorating conditions inside Christmas Island and all the problems that are associated with mandatory detention.

"The Rudd Government has seen fit to continue those Howard government policies and it is now reaping the whirlwind.

"All the consequences, all the difficulties that were faced by the Howard government, will be visited on the Rudd Government because they have perpetuated the appalling conditions in mandatory detention."