Indian Navy commandos have boarded a hijacked Liberian-flagged vessel in the Arabian Sea and are now carrying out "sanitisation" operations, the navy said on Friday, without elaborating.

An Indian Navy warship intercepted the MV Lila Norfolk on Friday afternoon, less than a day after the navy received news that it had been hijacked off Somalia's coast in the North Arabian Sea.

In its latest update on the incident, the UK Maritime Trade Operations (UKMTO) agency said no unauthorised persons were found on board the vessel by military forces and all crew are safe and accounted for. "Vessel is proceeding out of the area," it said.

At least 15 Indian crew members were on board the vessel, which was hijacked near Somalia's coast and the navy received information about it on Thursday evening, Indian news agency ANI, in which Reuters has a minority stake, reported earlier, citing military officials.

The warship INS Chennai was diverted and deployed to assist the vessel, the navy said earlier in the day, adding that a naval aircraft flew over the hijacked vessel on Friday and had established contact with it.

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

It said earlier this week that it had investigated a large number of fishing vessel and boarded vessels of interest in the region.

The hijacking of commercial ships and attempted hijackings by suspected pirates near the Gulf of Aden and Arabian Sea regions resumed in December after a six-year lull. Experts believe this is because naval forces led by the U.S. have diverted their attention to the Red Sea to thwart Houthi attacks.

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.

Earlier this week, the navy said it had investigated a large number of fishing vessels and boarded vessels of interest in the North and Central Arabian Sea.

"India plays the role of a net security provider in the entire Indian Ocean region. We will ensure that maritime trade in this region rises from the sea to the heights of the sky," Defence Minister Rajnath Singh said last month of the increased surveillance in the region.

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

(Reporting by Krishn Kaushik and Shubham Kalia in Bengaluru; Writing by Shilpa Jamkhandikar, Editing by Christian Schmollinger and Michael Perry)