Rescuers at the site of an overturned sand-dredging vessel in the waters off southern Malaysia yesterday.

One person died, while 14 others - 12 Chinese, one Indonesian and one Malaysian - were missing after the dredger capsized off Parit Jawa in Johor's Muar district, officials said. Three other people were rescued.

Senior coastguard Sanifah Yusof told Agence France-Presse that divers searching for the missing crew members believed some could still be alive inside the overturned boat.

"We believe there are some crew trapped in the ship. The divers knocked on the body of the ship and got a response," he told AFP.

Three Chinese crew members were rescued after the authorities received reports that the JBB Rong Chang 8 had overturned at about 8.50am local time, the Malaysian Maritime Enforcement Agency said in a statement.

It was not clear what caused the accident.