Thirteen people are feared dead after an Indonesian police plane lost contact during a flight.

Its five crew members and eight passengers are feared to have died after police uniforms and other clothing were retrieved from the sea.

The aircraft P4201, which had been flying to the island of Batam near Singapore, dropped out of contact about 50 minutes after taking off from Bangka island.

Villagers found a seat and a bag containing a cellphone and police documents, a police chief said.

National Search and Rescue Agency chief Henry Bambang Soelistyo said rescuers were searching waters between Mensanak and Sebangka islands.

Local media, citing the Tanjung Pinang naval base commander, reported that bodies had been recovered by villagers.