The Indian Navy on Friday rescued the crew of a merchant vessel after its attempted hijack in the Arabian Sea and said it had not found any pirates on board.

An Indian Navy warship intercepted the Liberian-flagged MV Lila Norfolk bulk carrier less than a day after it received a report that the vessel had been hijacked about 460 nautical miles off Somalia.

About five to six armed people boarded the vessel on Thursday, according to a report received by the UK Maritime Trade Operations (UKMTO) agency, which said the ship’s crew had gathered in the ship’s citadel.

The navy said all 21 crew on board, including 15 Indians, had been evacuated and a warship was helping to restore power so the vessel can resume its voyage.

The vessel was destined for Khalifa bin Salman in Bahrain, according to British maritime security firm Ambrey. It was not immediately clear what it was carrying.

“The attempt of hijacking by the pirates was probably abandoned with the forceful warning by the Indian Navy, marine patrol aircraft, of interception by an Indian Naval warship,” the navy said in a statement.

The Indian Navy has increased its surveillance of the Arabian Sea after recent attacks in the region.

The hijacking and attempted hijacking of commercial ships in the Gulf of Aden and Arabian Sea resumed in December after a six-year lull. Experts believe pirates have been encouraged by US-led anti-piracy naval forces diverting their attention to the neighbouring Red Sea to thwart attacks there by Houthi rebels.

Data from the Indian Navy’s Information Fusion Centre - Indian Ocean Region shows at least three hijackings in December. The previous such incident was reported in 2017.

“The sudden revival in ship hijacking and attacks can only be attributed to the pirates’ willingness to take advantage of the fact that the focus of anti-piracy maritime forces has largely shifted from the Gulf of Aden to the Red Sea,” Abhijit Singh, head of the Maritime Policy Initiative at the Observer Research Foundation think tank in New Delhi, said.

India is not part of the US-led Red Sea task force.