A publicly listed Philippines salvor has been appointed to tackle what could be one of the country’s worst oil spills, following the sinking of a tanker.

Harbor Star Shipping Services has mobilised tugs and salvage equipment to “minimise the possible environmental damage resulting from the oil spill”, it said in a statement to the Philippines stock exchange.

The 1,415-dwt Terranova (built 2002), was carrying about 1,494 metric tonnes (11,000 barrels) of industrial fuel when it sank off the coastal town of Limay, in Bataan province, early on Thursday.

Manila-based owner, Shogun Ships Co, said the coastal tanker encountered five-metre waves and strong currents and tried to return to Limay with the help of a tug when it started listing.

The coastguard said on Thursday that an aerial survey suggested that the slick was more than 3.5 km-long.

Limay mayor Nelson David told local radio on Friday that the leak appeared to be of bunker fuel. It was not immediately clear if any cargo tanks had been breached.

A seafarer died while the other 16 crew members from the ship were rescued when their vessel sank off the coast of Limay town in Bataan province, as Typhoon Gaemi swept through the region.

A Tanzanian-flagged 599-gt cargo ship Fu Shun (built 1985) also sank off Taiwan with nine Myanmar seafarers on board. Three other ships also ran aground in Taiwan.

Protection and indemnity cover for the Terranova is provided by Steamship Mutual, a member of the 12-strong International Group of P&I Clubs that covers 87% of oceangoing shipping.

Shogun has entered into a salvage agreement with Harbor Star under Lloyd’s Open Form terms, which dictate the payment scale for the operation.

The two companies “entered into a no-cure, no-pay contract for the immediate salvage of M/T Terranova, including oil spill response operations to minimise the possible environmental damage resulting from the oil spill”, Harbor Star said in a statement to the Philippines stock exchange.

Coastguard spokesperson Armando Balilo said the tanker sank in shallow waters and siphoning the oil could be done within seven days.

“We are still preparing for the worst-case scenario to address the potential negative impact on the marine environment,” he said.

Shogun said that it was “cooperating fully with all anti-pollution efforts now underway”.