The Australian authorities have intercepted four boats carrying more than 150 suspected asylum seekers off the western Australian coast in the past two days.
The federal government is already investigating more mainland sites to house asylum seekers, to take the pressure off its already overcrowded Christmas Island detention centre
The federal Opposition says navy personnel feel they are no more than a taxi service to the high number of asylum seeker boats arriving in Australian waters.
Opposition defence spokesperson David Johnston says crews are constantly making trips from Ashmore reef to the Christmas Island detention centre.
