The Tamil Refugee Council claims at least 11 people who Australia has reportedly handed over to the Sri Lankan navy have been tortured by that country's intelligence services.

It has been a week since the Tamil community, refugee supporters and the media last heard from a boat close to Christmas Island carrying 153 Tamil asylum seekers.

They reportedly are, or have been, aboard an Australian Customs ship and, despite having claims for protection, will reportedly be, or have been, handed over to the Sri Lankan navy.

Tamil Refugee Council spokesman Aran Mylvaganam says he has spoken to a relative of people who were on the boat. 

"There were at least 11 people on this boat who had been arrested by Sri Lanka's intelligence forces and had been tortured," said Mylvaganam.

He said the 11 would appear to have genuine refugee claims, and there must have been more people on the ship in a similar situation. 

"There was at least a lot more, but 11 people have been accused of being members of the Tamil Tigers and were tortured by the Sri Lankan army.

"He [the relative] knows them. He was a close friend of these 11 people but he has at least five relatives on this boat who had been harassed by the Sri Lankan intelligence agencies in the past."

Asked if any on board were Tamil Tigers, Mylvaganam said that was unclear.

"We don't know it and he doesn't know it, but they were accused of being members of the Tamil Tigers. 

"They fled Sri Lanka to a refugee camp in India and from there got on a boat and came to Australia. If they are handed over to the Sri Lankan authorities we are certain their lives are in danger.

"Those who have been tortured in the past are at higher risk of facing more problems of the Sri Lanka intelligence agency. We are very worried.

"We have now got more information about these refugees and we know that if we don't keep an eye on them, the Sri Lankan authorities will torture them."

 (ABC)