The Philippines is investigating claims that the 2022-built tanker that sank off its coast causing an oil spill was a converted LPG carrier.

Justice Secretary Jesus Crispin Remulla said a witness had come forward to say that the Princess Empress was a twice “rebuilt scrap ship” that had been converted into a tanker, according to local reports.

The 1,100-dwt tanker, owned by RDC Reield Marine Services, based in Manila, went down in rough seas on 28 February carrying 800,000 litres of industrial fuel oil.

The slick has been spreading through coastal fishing communities and affecting some of the world’s most richly diverse marine environments.

Official documents showed that the ship was a 2022 newbuilding but inquiries are continuing into the claims, said the Maritime Industry Authority (Marina).

The director of Marina’s legal service, Sharon Aledo, told television network ABS-CBN that an inquiry was continuing into the incident which included the shipowners, “naval architects involved in the construction, the marine surveyors and also the classification society in this particular case”.

She said the company owned two other vessels.

The incident already has led to mixed messages about whether the vessel had the correct documents to sail.

Hernani Fabia, administrator of Marina, told a senate hearing earlier this week that documents had not been submitted.

The hearing heard that the ship had sailed without a permit on nine occasions before it sank, the Philippine Star reported.

But coastguard officials later posted pictures of a document on social media that appeared to contradict Marina’s position. The owner has insisted that the paperwork was in order, according to the Philippine Star.

Apology for massive spill

The owner has apologised for the spill and said it is doing everything possible to minimise the impact on the environment and clean up the spill.

The tanker has been located about 14 km off the island of Mindoro and nearly 400 metres below the surface, he said. Booms have been placed around the site and other efforts are being made to contain the spill.

The incident is likely to run up substantial claims but the vessel does appear to be fully insured.

The owner’s protection and indemnity insurance is placed with the Shipowners’ Club, which is a member of the International Group of P&I Clubs.

The International Oil Pollution Compensation Funds has also been studying the case to evaluate if it is eligible to be included in the scheme.