Rescuers have recovered the bodies of two crew members on an Iranian oil tanker that has been burning since it collided with a freighter last week in the East China Sea, according to Chinese state media.

Key points: The tanker was carrying 136,000 tonnes of highly flammable ultra-light crude oil

The tanker was carrying 136,000 tonnes of highly flammable ultra-light crude oil Three bodies have now been found, leaving 29 crew members still missing

Three bodies have now been found, leaving 29 crew members still missing South Korean officials warn the ship may continue burning for a month

State broadcaster China Central Television (CCTV) said the bodies were found on the lifeboat deck of the Sanchi on Saturday morning.

One body was recovered from the sea earlier this week, leaving 29 crew members still unaccounted for.

The ship, run by Iran's top oil shipping operator National Iranian Tanker Co, was carrying 136,000 tonnes of condensate, an ultra-light crude that is highly flammable, to South Korea.

It was equivalent to about 1 million barrels, and worth around $76 million.

There were 30 Iranians and two Bangladeshis working as crew onboard.

The salvage team recovered the voyage data recorder, or 'black box,' before leaving the vessel less than half an hour after boarding because the wind had shifted and "thick toxic smoke" had complicated the operation, the Xinhua newspaper said.

CCTV said rescuers were prevented from entering the crew living quarters by temperatures as high as 89 degrees Celsius.

Thirteen ships, including one from South Korea and two from Japan, were engaged in the rescue and clean up effort, spraying foam in an effort to extinguish the fire.

Intense flames, bad weather and poor visibility have all hampered rescue efforts.

South Korean fisheries officials had warned the tanker could continue to burn for as long as one month, and there were concerns the ship could explode and sink.

The cause of the collision remains unclear.

It is the second collision for a ship from the National Iranian Tanker Co in less than a year-and-a-half.

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.

Sorry, this video has expired Iranian oil tanker ablaze as rescuers search for missing mariners

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