At least 30 crew members of an Iranian oil tanker are feared to be dead after it collided with a Chinese freight ship and exploded in the East China Sea on Saturday night.

The oil tanker, which was on lease with South Korean company Hanwha Total, was on its way to Daesan in South Korea after its departure from Kharg Island in Iran.

Apart from possible loss of human lives, the collision and subsequent accident had resulted in oil spill in the sea. So far, one dead body has been recovered while the remaining crew members are still unaccounted for.

Rescue work at the site has been reportedly hampered due to poor weather conditions. While the extent of the oil spill is yet to be known, it could possibly be the worst since the 1991 offshore Angolan coast which saw an oil spillage of 260,000 tons, reported Reuters.

The oil tanker named Sanchi, owned by Iranian oil shipping operator National Iranian Tanker Co (NITC), crashed into the CF Crystal freight ship about 296km east of the Yangtze River Delta. The reasons of the collision are yet to be known.

Sanchi was having 136,000 tons of ultra light crude oil on board, of worth about $60m, and equivalent to just under one million barrels. The freight ship, on the other hand, was carrying grain from the US and was heading towards southeast Guangdong in China.

Chinese foreign ministry spokesman Lu Kang told reporters: “The Chinese government takes maritime accidents like this very seriously, and has already dispatched many search and rescue teams to the scene to carry out search and rescue.”

The Chinese authorities have also deployed ships at the accident location to clean the oil spill from the Iranian vessel.

While all 21 crew members of the Chinese freight ship were rescued, the same was not the case with the 30 Iranians and two Bangladeshis who were on the ill-fated oil tanker which was registered in Panama.