Search ends for boat survivors

Authorities have given up hope of finding any more survivors from the boat which sank off the Cocos Islands.

The Australian Maritime Safety Authority (AMSA) suspended the search for 11 missing people at 10.30am on Wednesday.

The boat, which was carrying 39 suspected asylum seekers towards Australia, sank at 11.15pm on Sunday, 350 nautical miles northwest of the Cocos Islands.

Two boys aged 13 and 14 are among the victims.

A group of 27 survivors and the body of one of the deceased are aboard the LNG Pioneer. The commercial vessel is expected to arrive at Christmas Island on Friday morning, where the group will be processed.

Two bodies were spotted in the water on Tuesday but could not be recovered.

Home Affairs Minister Brendan O'Connor said there was no hope of any more survivors.

"Medical advice received indicates that there is no further chance of survivability," he said in a statement.

"This is a tragic incident."

A spokesman for the LNG Pioneer said on Wednesday the survivors were generally all in good health, although one man had recovered from a high temperature.

He also understood the boat, and its 39 male passengers, had left Sri Lanka in early October.

"So I'd think they'd be pretty happy to have their feet on solid ground," the spokesman told AAP.

The LNG Pioneer, a private gas carrier, was one of the first to respond to the distress call.

The spokesman said the 20-plus crew was coping well and had enough food and supplies without the need to request assistance from the Australian authorities.

The ship's master and crew thanked the Australian Maritime Safety Authority on Wednesday for its help during the rescue.

"We thank the Australian Maritime Safety Authority and the team at its rescue coordination centre for their assistance and support," LNG Pioneer's parent company MO LNG Transport said.

"We are sad for the families of those who tragically lost their lives and look forward to disembarking the survivors for medical attention."

All survivors, including a 15-year-old boy, had been provided with food, clothing and medical help, where required, the company spokesman said.

It's expected the Sri Lankans will undergo medical and identity checks when they arrive at Christmas Island on Friday.