Three boats carrying more 214 people have been intercepted off the north-east coast of Australia since Friday.
HMAS Maryborough helped a vessel that sought assistance north-east of Christmas Island early on Saturday.
The vessel was earlier detected by a Customs and Border Protection surveillance aircraft.
AAP reports that initial indications suggest 54 passengers were on board.
On Friday a boat carrying 101 people was intercepted north of Christmas Island by HMAS Pirie, after being detected by an RAAF maritime patrol aircraft.
Border Protection Command said 97 passengers and four crew were on board.
A third boat carrying 56 passengers and three crew was intercepted by HMAS Bathurst northeast of the Ashmore Islands, also on Friday.
AAP reports passengers from all three boats will be transferred to Christmas Island for security, health and identity checks.