A Malaysian oil tanker carrying 900,000 litres of diesel has been hijacked and taken into Indonesian waters, according to authorities.

The Malaysian Maritime Enforcement Agency (MMEA) said in a statement on Tuesday that the ship, Vier Harmoni, had been located in the waters off Batam, Indonesia.

The MMEA said they had yet to confirm the identity of the hijackers.

The ship had sailed from the Tanjung Pelepas port, in Malaysia, on Monday.

Al Jazeera’s Step Vaessen, reporting from the Indonesian capital Jakarta, said hijackings have been increasing in frequency in waters off Indonesia.

The tanker was last seen around the Pulau Bintan island and Indonesian maritime authorities were coordinating with Malaysian officials on its whereabouts, she added.

“It’s also likely that the hijackers siphoned the oil into another tanker ship which they intend to sell on the black market,” Vaessen said.

In June last year, pirates hijacked the Orkim Victory, a Malaysian tanker, and pumped the oil from it into another tanker before releasing it.

[Source: Al Jazeera and agencies]