Officials said seven of the crew managed to swim across but the captain remained missing after the early morning crash when the anchored tanker was rammed by an empty cargo ship from behind in the Shela river.
“The oil is spilling off in the Shela river,” a coastguard official said in southwestern MonglaPort raising concerns about the impact of the leak on the rich biodiversity of the Sundarbans, which is criss-crossed by a wide networks of rivers and channels.
The tanker was anchored overnight in the Shela river on its way to a power plant in southwestern Gopalganj district carrying 357,664 litres of furnace oil.
Mongla Coast Guard’s contingent commander Captain Mehedi Masud told an online news agency that the ‘OT Southern Star 7’ was hit around 5 am at the Chandpai Range of Sundarban's West Zone in Bagerhat.
He said the accident was apparently caused by the early morning fog.
Police and coastguard officials said searches were underway to find out the missing captain while they feared he could be trapped inside the sunken vessel.
The Sundarbans forest, which covers 26,000 square kilometres in India and Bangladesh, is also the habitat of famous Royal Bengal Tigers.
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