TOKYO, July 30 (AFP) – A Japanese shipping company maintained that its oil tanker was likely attacked in the Strait of Hormuz a day earlier, dismissing reports it may have been hit by a freak wave.

Mitsui OSK Lines officials reiterated at a Tokyo press conference that crew members saw a flash and heard an explosion in the incident shortly after midnight local time on Wednesday in the waterway between Iran and Oman.

''There are some reports saying the tanker was hit by strong waves, but it's quite unlikely,'' said Mitsui safety management official Masahiko Hibino.

''We have not reached a conclusion, but we still suspect'' the tanker was hit by a blast, Hibino said of the mysterious incident some 18 kilometers (11 miles) off the coast of Oman, in which one crewman was slightly injured.

He said the company had not changed its stance since Wednesday when it said it suspected it had been attacked, perhaps by terrorists.

US and British naval officials were Thursday inspecting the ship, he said.

The Japan-bound vessel – crewed by 16 Filipinos and 15 Indians – was carrying 270,000 tonnes of crude oil but did not suffer a spill.

One of the crew saw a flash on the horizon at the time, while several other sailors heard an explosion, Hibino said, adding that the weather was fine and there were no reports of high waves in the region.

Hibino displayed images of the tanker, the M. Star, which showed damage to the railings, the loss of a life vessel, a shattered window, and broken furniture and fittings and shattered glass inside a dry cabin.

Pictures of the outside of the vessel – published earlier by the state-run Emirates News Agency WAM – showed an indentation several meters across in the hull, but no obvious burn marks or signs of an explosion.