There are reports that people on a boat carrying 73 suspected asylum seekers made a triple zero call before being found north of Christmas Island.
Home Affairs Minister Brendan O'Connor says that sailors aboard HMAS Wollongong also discovered four crew on board the boat on Friday.
"The people have been transferred to Christmas Island where they will undergo security, identity and health checks and their reasons for travel will be established," Mr O'Connor said in a statement.
ABC Online reported that the boat had made the emergency call on Thursday.
"While their nationality is yet to be confirmed, if these asylum seekers are Sri Lankans or Afghans, the processing suspension introduced by the government on 9 April 2010 will apply," Mr O'Connor said.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
Security logjam
Meanwhile, the Australian newspaper is reporting that up to 150 asylum seekers are being kept in detention because the Australian Security Intelligence Organisation (ASIO) can't decide if they pose a security threat.
Some are said to have been in detention for more than 12 months, contributing to detention centre overcrowding.
The ASIO has declined to comment.
