The RAN's shore establishment in Darwin, HMAS Coonawarra, is to have a 900-person temporary immigration reception and processing centre, the Immigration Minister, Mr Phillip Ruddock announced last month.

The centre will be used on an "as required" basis.

The Minister Assisting the Minister for Defence, Mr Bruce Scott later announced that he had directed Defence to develop measures to deal with concerns that might arise from families living within Coonawarra.

"Options include increased security arrangements for those who reside within the naval base and the married quarters and a choice for individuals and families to relocate to Defence Housing properties within the Darwin area, should they so wish," Mr Scott said.

Mr Scott said that in addition to Coonawarra, temporary immigration processing centres will be set up at the Singleton Military Area, and the El Alamein at the Cultana Training Area near Port Augusta.

The announcements of the new centres came after about 470 suspected illegal immigrants arrived at Christmas Island.

This takes the number of suspected illegal immigrants detained by Australian authorities in the period August 1 to August 23 to over 1350.

More parties of immigrants were reported on their way.

In one arrival, HMAS Launceston was called to assist the Customs patrol vessel Botany Bay process 230 people, almost all from the Middle East, who arrived at Ashmore Reef on a 30-metre-long Indonesian inter-island ferry.

After processing, the 230 were taken to the mainland by the Immigration Department chartered ferry Sampson Explorer.

LCDR Ken Burleigh and his Ship's Company went on to arrest nine Indonesian fishermen for taking trepang in Australian-controlled waters near Hibernia Reef.

Launceston landed the nine at Broome and continued patrols.