NEW DELHI: The India-bound merchant vessel, 'which came under attack by a drone', is being escorted back to native shores by Coast Guard ship Vikram in the Arabian Sea, officials said on Sunday.

According to officials, the merchant ship, hit by a suspected drone on Sunday, requested to be escorted by the ICGS Vikram. Both are expected to reach off the Mumbai coast on Monday.

Indian Coast Guard Dorniers are also airborne to keep an eye on the merchant vessels and carry out surveillance in the area, officials added.

A Pentagon spokesperson told Reuters earlier that the motor vessel, CHEM PLUTO, a Liberia-flagged, Japanese-owned, and Netherlands-operated chemical tanker, was struck at approximately 10 am local time (6 am GMT) today in the Indian Ocean, 200 nautical miles from the coast of India, by a one-way attack drone fired from Iran.

Meanwhile, the Indian Navy said earlier it has opened an investigation into whether the drone used to attack the vessel was launched from long-range or a nearby vessel. The incident comes as the latest illustration of the growing regional tensions after the October 7 Hamas attacks on Israel.

The Pentagon said this was the "seventh Iranian attack on commercial shipping since 2021". MV Chem Pluto, with 20 Indian and one Vietnamese crew member on Saturday caught fire after it was attacked by a suspected drone.

It was later secured by the Indian Coast Guard (ICG), the ICG said in an official statement. The merchant vessel reportedly commenced its voyage from the UAE on December 19 and was bound for New Mangalore port with an arrival date of December 25.

According to the official statement, on December 23, the Indian Coast Guard Maritime Rescue Coordination Centre in Mumbai received information regarding a fire onboard MV Chem Pluto, reportedly attacked by a suspected drone strike or aerial platform.

The Indian Coast Guard Maritime Coordination Centre (MRCC), which established real-time communication with the vessel's agent, ascertained no loss of life and assured all assistance. It was also learned that the vessel fire had been doused by the crew. To augment the vessel's safety, MRCC Mumbai has activated ISN and immediately diverted other merchant vessels in the vicinity of Chem Pluto for assistance.

"The Indian Coast Guard also pressed Offshore Patrol vessel Vikram and Coast Guard Dornier maritime surveillance aircraft into action for rendering assistance to Chem Pluto. The Coast Guard Dornier aircraft has sanitised the area and established communication with Chem Pluto. The vessel has started making its way towards Mumbai after undertaking damage assessment and repairs on its power generation systems," the statement further read.