Indonesian authorities say two Sri Lankan asylum seekers have died while trying to get to Australia, but more than 20 others have been rescued from their crippled boat overnight.
The ABC has been told that a local fisherman found the crippled boat last night and alerted guards on the Island prison of Nusakambangan off central Java.
Indonesian police, the navy and prison authorities then started a rescue operation that was hampered by tough conditions through the night.
The head of immigration at nearby Cilacap, Syamsul Bahri, says 22 people were rescued but two had died at sea, and another is missing.
He says the Sri Lankans had been at sea for two months, attempting to get to Australia, but the boat's engine failed and they ran into a reef off Indonesia.
He says the survivors will be taken to immigration detention.