Chennai, Sep 6 (IANS): The fire in the burning oil tanker 'New Diamond' with about 3,00,000 tonnes of crude oil for Indian Oil Corporation (IOC) was doused on Sunday and the situation is being monitored to prevent any reignition, said an Indian Coast Guard official.

"The fire has been doused. However, the situation is being monitored and action being taken to prevent reignition. Technically it is said the fire is under control as the temperature of the adjoining plates has to be reduced to prevent reignition," a Coast Guard official told IANS.

According to the Coast Guard official, the fire in one of the ship's ready to use fuel tanks was put out once but the second one got ignited.

"The total quantity of the fuel for the ship engine was about 1,700 tonne," the official added.

Six ships, one Dornier aircraft and one helicopter of Indian Coast Guard along with one Lankan Navy ship and aircraft and four tug boats battled the fire and monitored any oil slick.

A coordinated action of Coast Guard ships and Lankan Air Force brought the fire under control.

The Coast Guard ships used foam and water while the Sri Lankan Air Force dropped dry chemical powder to douse the fire.

The 20-year-old very large crude carrier (VLCC), sailing under the Panama flag, reported fire on Board on Thursday when it was about 37 nautical miles off the coast in Sri Lankan Exclusive Economic Zone.

The New Diamond oil tanker departed from Mina Al Ahmadi, Kuwait on August 23 and was headed to India's Paradip port.

The oil tanker was expected to reach Paradip in Odisha on September 5 where the IOC has a large refinery.

According to the Coast Guard, the vessel reported a major explosion in its engine room while it was on its way to Pradip in Odisha where the IOC has a large refinery.

The first information about the vessel fire was received at the Coast Guard Maritime Rescue Co-Ordination Centre (MRCC) in Mumbai.

Soon the Indian Coast Guard mobilised several of its assets from different locations and sent them to the scene of action.

"Fighting a ship fire on mid sea is not an easy task and more so in the case of an engine room fire. The engine room is located at the bottom of the oil tanker. The ships that are involved in fire fighting throw foam and water from the top and it has to reach the location of the fire," the Coast Guard official added.

"So, four days of fire fighting operation is not unusual. Further the ship metal structures are also painted with would add fuel to the fire," he added.

The Coast Guard had earlier observed a two-metre crack near the port aft portion of New Diamond, 10 metres above the waterline.

A Coast Guard official, told IANS that the crack has not grown further.

On Saturday, the burning oil tanker was safely towed away further from the Lankan coast to prevent its drift towards shallow waters.

The next course of action as regards the oil tanker will start after the fire is put out and ensured reignition doesn't happen, said a central government official had told IANS.

"The immediate task on hand is to put out the fire and ensure that there is no reignition. Only after that the various suitable action options will be considered," the official told IANS preferring anonymity.

The official said the decision on whether to tow the vessel, if so to where or whether to transfer the crude to another oil tanker mid-sea (double banking-ship to ship transfer) will be decided after the New Diamond's condition is ascertained and the vessel is stabilised.

Meanwhile, officials of the IOC were not available for comment.