A boat carrying an estimated 150 asylum seekers has overturned off the coast of Australia's remote Christmas Island, less than a week after a similar incident killed up to 90 people.

Two Australian merchant ships are collecting survivors at the scene of the capsizing in the Indian Ocean, about 200 kilometers north of Christmas Island. Australian authorities say two warships and a military aircraft will join the search later Wednesday.

There is no immediate information on the number of survivors. Australian maritime officials say the conditions at sea are fair, but not ideal.

Last week, a boat carrying about 200 people went down in the Indian Ocean as it made its way to Australia. Rescuers managed to save 110 people. Seventeen bodies were recovered, but no other survivors have been found.

Australia is a major destination for people fleeing impoverished, war-torn countries such as Afghanistan, Iraq and Sri Lanka. Many of them are crammed into crowded detention centers on Christmas Island and the Australian mainland.