A tanker leased by the Iranian Offshore Oil Company (IOOC) sank near a drilling rig belonging to Soroush Oilfield in the Persian Gulf on Wednesday. The crew was rescued.
According to an IOOC report published on Saturday, the engine room of Masrour tanker was flooded at 14:30 local time on Wednesday, Mehr News Agency reported.
IOOC is one of the world's largest offshore oil production companies, with over half a century of experience. The company handles one-third of Iranian oil export.
Saeed Hafezi, the IOOC chief, said his company extracted over 144 million barrels of oil from oilfields located mainly in the Persian Gulf and Oman Sea in the last fiscal year that ended in March.
Following the captain’s request for help, a marine operation unit in the nearby Bahregan zone sent a boat equipped with pump to drain the water from the engine room that was weighing heavily on the tanker.
A second vessel with a stronger pump and a rescue boat were also dispatched from the Kharg Island and rescued all 12 crew members onboard. Efforts to lead the half-sunk tanker to the coast were not successful and it sank. The tanker's owner was not immediately known.
Iran operates one of the world's largest tanker fleets ahead of regional rival Saudi Arabia as well as Qatar, Oman and the UAE, according to the United Nations' 2015 Maritime Transport report.
Reportedly, Iran has 42 very large crude carriers (VLCCs), nine Suezmaxes, five Aframaxes and several other ships, with the fleet’s average age at around 8.5 years.
Iranian tankers carry cargo under the certification of the international classification institute Lloyd's Register. In addition, they are all covered by international insurance firms.
The European Union introduced tougher sanctions against Iran in early 2012, including a ban on the insurance of Iran tankers and shipment of its crude oil and petroleum products. The restrictions were eased in January after the nuclear agreement Tehran signed with the world powers.