DHAKA: Bangladesh on Saturday launched an intensified manual campaign to clean up seepage from a sunken oil tanker in the Sundarbans as authorities could not reach a decision on using chemicals to neutralise the oil during the past four days.

Officials and witnesses said the forest department engaged nearly 100 boats to collect the furnace oil spilt from the tanker which sank in the Shela river in the Sundarbans four days ago after being hit by a cargo vessel.

“At least 200 hired workers in nearly 100 engine and country boats have started a campaign to collect the oil from rivers and canals,” a local journalist told Gulf News over phone from the scene.

He said the workers were loading the boats with the oil which they were collecting manually using the traditional equipment and depositing those in tanks in a nearby boat terminal.

“The oil collection will continue until further notice,” a local forest official meanwhile told a TV channel from the scene.

Forest official Amir Hossain Chowdhury, however, said they were expected to reach a decision on the modus operandi of the oil cleanup by later today.

Fears of more deadly impacts so far prevented authorities to spray oil neutralising chemicals as planned initially as most experts warned the chemicals could cause more harm to the biodiversity and aquatic life in the world’s largest mangrove forest.

Director general of environment department Mohammad Shahjahan told newsmen that they sent the specimen of the chemicals for analysis to their own laboratory and the testing facilities of the Bangladesh University of Engineering and Technology (BUST).

“But we are yet to get their reports and suggestions ... so until now we cannot give permission for its use in the Sundarbans,” he said.

The authorities earlier had asked locals to collect the furnace oil using fishing nets, sponges or any other manual means and sell it to the state-run Padma Oil Company.

The seepage spread in the Shela and the Pashur rivers and over 20 canals which criss-cross the Sundarbans, in the past four days while officials found four out of six chambers of the tanker, carrying 358,000 litres oil, damaged to cause the spill as it was salvaged two days ago.

Seven members of the sunken tanker’s crew managed to swim ashore, but their captain Mokhlesur Rahman was still missing as of Friday evening.

The authorities have filed a lawsuit against the owners of both ships.

Bangladesh is yet to seek any overseas assistance to remove the oil but shipping minister Shahjahan Khan yesterday told the BBC radio that a London-based team offered assistance.

Several Bangladeshi newspapers carried pictures of sickened creatures like lobsters due to the disaster while the mass circulation Prothom Alo said the crocodiles visibly disappeared from their abodes near the accident site.

Officials said oil spill from the sunken tanker affected seven young saltwater crocodiles at Karamjal Wildlife Reproduction Centre but they were also concerned about the fate of dolphins in the region as the site is their natural abode.

But the experts feared the seepage to cause deadly impact on the mangrove vegetations as well as the submergible plants were completely covered in the oil while the big trees’ barks were smeared with oil two-three feet from above the ground.

The manual cleanup campaign came as authorities on India’s eastern coast are on alert with additional director of India’s Sundarban Biosphere Reserve Pradeep Vyas saying “we are taking all precautionary measures”.

The Sundarbans include large swaths of protected areas that host a diverse wildlife, including threatened species such as the Royal Bengal tiger, rare dolphins and the estuarine crocodile.

The Sundarbans cover 26,000 square kilometres in India and Bangladesh while it is criss-crossed by a wide network of rivers and channels.