More than 1,000 tons of fuel oil have leaked from a stranded Japanese-owned freighter that ran aground off Mauritius, Mitsui O.S.K. Lines Ltd., the operator of the vessel, said Sunday.

Mitsui O.S.K. Lines Executive Vice President Akihiko Ono apologized for the incident at a news conference in Tokyo, after the island nation in the Indian Ocean declared a state of environmental emergency over the fuel leakage on Friday.

"We're terribly sorry," Ono said as he vowed to make all-out efforts to resolve the case.

As of Sunday, a massive amount of heavy oil had washed ashore along the coast of Mauritius, sparking concerns about damage to the country's tourism industry and the impact to endangered animals such as indigenous wild birds and sea turtles.

The Panama-flagged bulk carrier Wakashio ran aground off Mauritius at 7:25 p.m. on July 25 local time, according to Nagashiki Shipping Co., the owner of the ship.

Leakage of fuel oil began Thursday morning when a fuel tank suffered a crack, the Okayama Prefecture-based company said.

==Kyodo

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