Ships and aircraft from South Korea and the USA are aiding in rescue efforts, which have been hampered by fierce fires and poisonous gases that have engulfed the tanker and surrounding waters.
"Unfortunately, up to this moment, there is no news of the crew", he said. The tanker's crew of 32 are missing; one unidentified body has been recovered.
It wasn't immediately clear what caused the collision, which happened in open seas rather than a narrow channel where such accidents are more common. CF Crystal sustained significant damage to its bow in the crash (see photo below, courtesy of Ministry of Transport, People's Republic of China) and has been escorted to an anchoring point for investigation.
The vessel's cargo is worth around US$60 million at current crude oil prices. "We can not say all of them are died, because rescue teams are there and providing services".
The burning oil was making it hard to get close to the tanker and search for missing crew members, Iranian authorities said.
Reuters reports the collision "has the potential" to be the worst oil spill since 1991, when 260,000 tonnes leaked off the Angolan coast.
The size of the oil spill from the oil tanker and the extent of the environmental harm it caused is not known.
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The protesting royals also demanded compensation for the execution of their cousin, belonged to the royal family. The Gulf kingdom has also intensified efforts to boost employment of its own citizens.
The Sanchi was built in 2008, had at least four previous names and was previously flagged in four other countries, according to the International Maritime Organization and MarineTraffic, a ship monitoring service.
The Sanchi was loaded with condensate, a form of oil that only remains in liquid form under specific conditions and is more volatile compared with crude oil.
The Sanchi tanker, leased by Hanwha Total Petrochemical Co Ltd, had "valid foreign insurance", Iranian oil ministry spokesman Kasra Nouri told Iran's state television.
The tanker had been sailing to Daesan, South Korea from Kharg Island, Iran, according to Reuters ship tracking data.
Hanwha Total was not immediately available for comment.
The incident also marked the first major maritime incident involving an Iranian tanker since the lifting of global sanctions against Iran in January 2016. In August 2016, one of its tankers collided with a Swiss container ship in the Singapore Strait, damaging both ships but causing no injuries or oil spill.
The Hong Kong-registered cargo ship, CF Crystal, was carrying 64,000 tonnes of grain from the United States to Guangdong, a southern province of China. Norwegian ship insurer Skuld has confirmed it was the lead hull insurer for the tanker and the protection and indemnity (P&I) insurer for CF Crystal.