A radical group branding itself 'Brigades of Abdullah Azaam' claimed responsibility for the July 28 bombing of the Japanese oil tanker 'M Star' in the straits of Hormuz located between Iran and Oman, the US monitoring group SITE reported.
The little known group is named after Palestinian origin Islamic preacher Abdullah Azzam who was a prominent Mujahideen commander against Soviet forces in Afghanistan. He was killed in a blast in Pakistan in 1989 and buried in Peshawar.
The Japanese company Mitsui OSK Lines had earlier reported that one of its tankers appeared to have been hit by an explosion in the waterway through which 70 per cent of the world's oil flows.
The group said the attack was carried out in the name of Omar Abdul Rehman, the Egyptian Blind Sheikh, at present in the US for his role in the 1993 world trade centre bombing in New York.
The Japan-bound vessel, which had a crew of 16 Filipino and 15 Indians, was carrying 270,000 tonnes of crude oil, but did not suffer a spill.
An Indian crew member had reported seeing a flash on the horizon, while others heard a powerful explosion. But the tanker did not suffer any damage and arrived on its own steam to berth in UAE, where investigations are being carried out.
One crew member, who was not identified, was injured in the explosion, which caused minor damage across the tankers' hull, according to pictures published by the state-run UAE news agency WAM.
US Navy, which also reported the incident, has powerful elements of its 5th fleet based in the waterway.