Authorities in the Philippines think they have located the ship that sank last week off the coast of a central province as they raced to determine the extent of an oil spill that has forced a fishing ban and to prevent more environmental harm.

The environment ministry said in a statement on Monday that the tanker, the MT Princess Empress, is believed to be resting at roughly 1,200 feet (366 meters) below sea level, off the province of Oriental Mindoro. However, the information still has to be verified.

A remotely operated autonomous vehicle would be deployed to help determine the exact location of the tanker, it said.

Authorities want to know how much oil is inside and how to pump the remainder out and stop any leaks, experts said.

The vessel was carrying about 800,000 liters (211,338 gallons) of industrial fuel oil when it suffered engine trouble on Feb. 28 in rough seas, according to the coast guard.

It was not immediately clear what caused the Philippine-flagged vessel to sink but all 20 crew members were rescued before it went down.

Spilled oil had been detected on the shore and in coastal waters near the site where the vessel is thought to have sunk, forcing the government to declare a state of calamity in nine towns in Oriental Mindoro. This means emergency funds can be channeled directly to affected communities, including those hit by the fishing ban imposed by authorities during the clean-up.

“When I catch fish, my everyday earnings go to my children and to the food that we eat. It is a very big problem that this oil spill happened,” said 55-year-old fisherman Florante Favroa.

“It is a very huge loss for us, we have no more resources,” he said.

Swimming has also been banned in affected areas, with the tourism ministry expressing concern that the oil spill could affect three of the country’s world-class dive destinations like the Verde Island passage and Apo Reef in Mindoro, and the World War II Wrecks in Palawan.

About 36,000 hectares (88,958 acres) of coral reef, mangroves and sea-grass were potentially in danger of being affected by the oil slick, according to marine scientists at the University of the Philippines.

“Let me assure you, the damage done directly on the environment and on our people’s livelihood will be given corresponding compensation depending on what is stipulated in the compensation guidelines,” Dolor told a media briefing.

The tanker’s owner, RDC Reield Marine Services Inc., has contracted local agencies, Harbor Star Shipping Services and Malayan Towage and Salvage Corp., for the cleanup.

“The situation is very difficult…because of the weather. If sea conditions are bad, it is also unsafe for our contractors to work,” Rodrigo Bella, vice president of Harbor Star, told the media briefing.

The two contractors would shoulder all expenses initially, including paying residents hired for cleanup jobs, Dolor said.