Oil spill threatens rare dolphins in Bangladesh

Bangladeshi fishermen using sponges and sacks began cleaning up a huge oil spill in a protected area that is home to rare dolphins after some environmentalists had warned of an ecological "catastrophe".

Thousands of litres of oil have spilled into the protected Sundarbans mangrove area, home to rare Irrawaddy and Ganges dolphins, since a tanker collided with another vessel on Tuesday.

The government has sent a ship carrying oil dispersants to the area, which is inside one of three sanctuaries set up for the dolphins.

But environmentalists say the chemicals could harm the delicate ecology of the Sundarbans, a Unesco world heritage site.

The head of the local port authority told reporters that fishermen would use "sponges and sacks" to collect the spilled oil, which has already spread over an 80 km area.

But Amir Hosain, chief forest official of the Sundarbans, admitted authorities were in the dark about what to do.

"This catastrophe is unprecedented in the Sundarbans and we don't know how to tackle this," he said.