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STOCKHOLM, July 14 (Reuters) - Norwegian shipping company Stolt-Nielsen's SNI.OL chemical tanker Stolt Magnesium was attacked in the Arabian Sea off the coast of Oman on Tuesday, business daily Finansavisen reported, citing the company.

The ship was hit by "an explosion from an unidentified external object", causing a fire in the engine room, but everyone on board was safe and accounted for, the company told Finansavisen.

Stolt-Nielsen did not immediately respond to a request for comment.