Customs says the 80 men, women and children were taken directly to Darwin on January 7 because of rough seas near Christmas Island. At the time, the Immigration Department said that was only a stop-gap measure.

Now the group are being transferred from the mainland to Christmas Island. Five Indonesian nationals who were allegedly crew on the boat have been flown to prisons in Brisbane and Sydney. At the same time, a group of 44 people being held in detention on Christmas Island are being moved to Darwin.

The Immigration Department there are 2,715 people being held on Christmas Island at the moment - about 100 above the capacity of the facility. It says so far this year one person in detention has been deported. The department says he is an Iraqi national but they cannot confirm which country he has gone to.