After receiving a distress call on Saturday night, the Indian warships established contact with the captain of the merchant vessel who had locked himself in a strong room along with the rest of the Filipino crew.

“An Indian Navy helicopter undertook aerial reconnaissance of the merchant vessel … to sanitise the upper decks of the merchant ship and ascertain the location of pirates, if still on board,” a statement from the defence ministry said.

Emboldened by the helicopter cover and on receiving the all-clear signal that no pirates were visible on the upper decks, some crew members gradually emerged from the strong room.

They searched the ship and confirmed that the pirates had fled overnight.

A boarding party from the nearby Chinese Navy ship then arrived on the merchant ship, while the Indian Naval helicopter provided air cover for the rescue operation.