A survey ship Express-54 of Belgium-based company Jandinul -- engaged in excavating the Rabnabad channel -- capsized due to a leak in Payra Port of Patuakhali today.

The survey vessel sank at the inner side of the Rabnabad channel, about seven nautical miles south of the fair buoy at Payra Port this noon, confirmed Capt SM Sharifur Rahman, harbour master of Payra Port, reports our Patuakhali correspondent.

However, all the 12 crew members present -- 10 Indonesian and 2 Bangladeshis -- aboard the ship were rescued and unhurt, Sharifur told The Daily Star.

"During the excavation work of Payra Port channel, water got into the ship's machine room through a hole. Realising the matter within minutes, the ship's crew sought help from a nearby fishing trawler," he said.

Later, the company and Payra port's tugboat rushed to the spot and brought everyone to safety.

Efforts are on to rescue the sinking ship, added the harbour master.