More than 700 migrants from Bangladesh and Myanmar have been rescued from a sinking boat off Indonesia’s coast.
Reports say another boat was turned back by the Indonesian navy.
The fate of another vessel of stranded migrants off the coast of Thailand is unclear after it was towed out of Thai waters.
Human Rights Watch has warned of deadly “human ping-pong” in the Andaman sea, where thousands more are believed to be adrift, struggling to land.
Rohingya Muslims have been leaving Buddhist-majority Myanmar, also known as Burma, because they are not recognised as citizens of the country and face persecution. Many of the Bangladeshis at sea are thought to be economic migrants.
They attempt to flee every year during the non-monsoon season, but the smugglers who take them to Thailand have been scared by a recent Thai crackdown and instead they are reported to have been abandoned at sea.
An Indonesian police chief in Aceh told AFP news agency that he believed the rescued boat had already been pushed out of Malaysian waters by Malaysia’s navy. He said it was sinking and towed to shore by fishermen. Medical officials said eight of the migrants were critically ill.