A Japanese supertanker in the Indian Ocean has spilled as much as 4,500 tons of crude oil after a collision with a cargo vessel in distress.

Thousands of tons of oil have leaked into the Indian Ocean after the two ships collided about 500 kilometers west of Great Nicobar Island between Sri Lanka and Indonesia.

The Japan bound supertanker was attempting to rescue, in rough seas, the crew of the cargo vessel, which had caught fire.

The tanker is owned by Mitsui O.S.K. Lines. Company spokesman Kenji Shikano tells VOA News the Bright Artemis was carrying 250,000 tons of crude when the accident happened.

Shikano says the collision ruptured two of the ship's oil tanks. He says none the crew was injured and the leak was contained after the remaining oil in the damaged tanks was transferred to other tanks.

Mitsui O.S.K. says the tanker is under way again, searching for a port where it can make repairs.

The crew of the Singaporean-flagged cargo vessel, the Amar, has reportedly been rescued.

The Bright Artemis, built 24 years ago in Japan and registered in Singapore, had loaded the light crude in Oman and Saudi Arabia.

Mitsui O.S.K. officials say the accident happened when a gust of wind blew the 10,000 OI ton cargo vessel into the supertanker. The collision caused a five-meter long, one-meter high gash in the bigger vessel's starboard hull.

Officials of the Japanese company say they have notified the Indian and Singaporean coast guards about the incident.