Malaysian maritime authorities said on Tuesday that an oil tanker carrying 900,000 litres of diesel has been hijacked and taken into Indonesian waters.

The Malaysian Maritime Enforcement Agency (MMEA) said in a statement that the ship, Vier Harmoni, was sailing from Tanjung Pelepas port in Malaysia on Monday when it was seized. It was carrying diesel with an estimated value of RM1.57 million (S$529,000).

The MMEA director-general Ahmad Puzi Ab Kahar tweeted on Wednesday that the ship was currently believed to be in the waters off Batam, Indonesia.

"#MTVierHarmoni and its load is believed to have been hijacked, carrying 900,000 litres of diesel worth RM1.57mil," he said in a tweet.

MMEA launched an investigation but the identity of the hijackers is not yet known.