DHAKA (AFP) - The Bangladesh Navy has now recovered 20 bodies of fishermen who were tied up and thrown into the deep sea in an apparent pirate attack, an officer said on Tuesday.

The bodies were found in the Bay of Bengal, where pirates have created a reign of terror by routinely robbing, kidnapping and extorting money from fishermen working along the coastline.

"Today our boats have found 17 dead bodies floating about 12km west of the lighthouse of Kutubdia Island," navy commander Mustafizur Rahman told AFP. Three bodies were recovered by a fishing boat on Monday.

"All the bodies were in decomposed state. They had their hands tied up and were thrown in deep sea," he added.

Deputy police chief in Cox's Bazaar town, Imran Bhuiyan, told AFP that the pirates appeared to have thrown the men into the sea alive and stolen the engine, fishing nets and catch on the fishing boat.

Last August, Bangladeshi authorities said they had rescued at least 60 fishermen abducted by pirates in the Bay of Bengal, but attempts by naval and air forces to crack down on criminal activity at sea have proved futile.