SYDNEY: Australian authorities said Monday they had called off a major air and sea search for survivors from a boat carrying at least 55 asylum-seekers which disappeared suddenly off a remote Indian Ocean territory.

Officials late Sunday halted the search for the vessel off Christmas Island -- which was seen before it went down carrying men, women and children -- after failing to find anyone alive.

Up to 13 bodies were spotted in the water during the extensive search. But Customs said staff were occupied with a number of "high-priority operations" in Australian waters and would not be able to recover the bodies on Monday.

"All Border Protection Command vessels and aircraft have been released from the search for survivors," Customs said in a statement.

"No attempts to recover the deceased are being made today."

Customs said border protection vessels and aircraft "are currently involved in a range of high-priority operations in waters near Christmas Island and elsewhere".

"Our priority is responding to other vessels which may require assistance, and preventing any further loss of life," the statement said.

"If operations permit, Border Protection Command will, where it remains feasible and without further risk to life, endeavour to recover any bodies which may be relocated."

The stricken vessel was initially spotted by a Customs plane off Christmas Island on Wednesday. But when a boat attempted to intercept it the following day it had vanished.

Thirteen bodies and an upturned hull along with other debris were subsequently spotted.