Port authorities, however, deny the charge and say they have taken all essential steps.

'The Gahirmatha Marine Sanctuary is perilously close and an oil slick can easily spread to this area, affecting the world famous mass breeding grounds of the Olive Ridley sea turtles,' Mohanty said.

A letter was written Wednesday to the state Pollution Control Board to issue directions to the port trust authorities to undertake immediate measures, he added.

'Besides, I had sent a fax message on Sep 11 to the Chief Wildlife Warden of the Orissa government, warning him about the impending oil spill and the likely adverse impacts on the rich marine life of the sanctuary,' said Mohanty, who is also a member of the National Board for Wildlife.

'The migratory Olive Ridley sea turtles are expected to arrive by the month-end and it would be a disaster if these materials pollute the area before their arrival,' Mohanty warned.

A section of the media Monday said the ship had spilled oil and a thick film of black crude oil was visible on the sea near Paradip and that dead fish lay scattered on the shore.

But the port trust said the spill was from the service tank of the engine room and was negligible.

'Out of the 924 metric tonnes of oil, 900 metric tonnes are inside a double bottom tank fully secured and are very safe and cannot be released easily,' the port trust said in a statement Tuesday.

However, D.K. Behera, a scientist of the state Pollution Control Board, said he found oil patches on the beach.

'Although the furnace oil is in a sealed tank and in seawater, it is under pressure. We cannot rule out the possibility of spillage,' Behera told IANS after inspecting the site.