The Indian Navy announced on Saturday that it was tracking a cargo tanker that had been boarded by unidentified attackers believed to be Somali pirates in the Arabian Sea.

The Indian Navy said in its statement that the Maltese-flagged ship MV Reon, with its 18-member crew, sent a distress message on the UK’s maritime trade operations portal on Thursday indicating that six unidentified people had boarded the ship.

She added that the Navy responded to the distress call by sending an anti-piracy warship and a maritime patrol aircraft to locate the ship and assist it.

The plane flew over the hijacked ship early Friday, and since then it has been continuously monitoring the movement of the ship, which the Indian Navy said was heading towards the coast of Somalia. It added that its warship, which was deployed in the Gulf of Aden to conduct anti-piracy patrols, also intercepted the carrier early Saturday.

Private intelligence firm Ambrey and the British Maritime Trade Authority confirmed that the ship Ruin, operated by Bulgarian shipping company Navibolgar, was off the Yemeni island of Socotra when it was seized on Thursday.

Bulgarian authorities said that the ship's crew were citizens of Angola, Bulgaria and Myanmar.

Bulgarian Foreign Minister Maria Gabriel also indicated to reporters on Friday that: “The necessary steps have been taken to pass information to all foreign partners and institutions that we will rely on to provide assistance.”

No group immediately claimed responsibility for the attack. However, suspicions immediately fell on pirates from Somalia, whose activity has declined in recent years.

Somali piracy has declined in recent years, but there are growing fears it could resume amid political uncertainty in the country and broader chaos in the region, which has included attacks on ships by Yemen's Houthis.

On Friday, the UK's maritime trade operations issued a warning to shipping companies, saying the Rioon's security chief "believes the crew is no longer in control of the vessel", while the EU's anti-piracy force in the region confirmed that the Spanish frigate Victoria was on its way. To intercept “the alleged ship believed to have been hijacked by pirates.”