An oil tanker carrying 900,000 litres of diesel has been hijacked and taken into Indonesian waters, Malaysian maritime authorities say.
The Malaysian Maritime Enforcement Agency (MMEA) said in a statement on Tuesday that the ship, Vier Harmoni, has been located in the waters off Batam, Indonesia.
The MMEA said they have yet to confirm the identity of the hijackers.
The ship, which sailed from the Tanjung Pelepas port in Malaysia on Monday, was carrying diesel with an estimated value of 1.57 million ringgit (NZ$540,000).
Vier Abdul Jamal, chief executive of the ship's owner Vierlines Asia Group, said the Indonesian-flagged vessel has 10 Indonesian crew on board and is currently chartered by another company.
The charterer and the harbour master where the vessel was being loaded lost contact with Vier Harmoni on Tuesday night and its tracking device is not active, he said.
The vessel could be hijacked, sunk or suffering engine problems, he said.
Malaysia's Maritime Enforcement Agency chief Ahmad Puzi said the agency has launched an investigation into the incident.