The attack took place around 10 am local time (0600 GMT) and caused no casualties aboard the Japanese-owned vessel, it said, adding that a fire was extinguished.

The US military "remains in communication with the vessel as it continues toward a destination in India," it added.

The Pentagon statement said the Chem Pluto ship flew under a Liberian flag and was operated by a Dutch entity.

The drone strike occurred 200 nautical miles (370 kilometers) off the coast of India, it said, adding that no US Navy vessels were in the vicinity.

There was no immediate claim of responsibility for the strike which came amid a flurry of drone and missile attacks by Yemen's Iran-backed Huthi rebels on a vital shipping lane in the Red Sea.

The Huthis say they are conducting the attacks in solidarity with Palestinians in the besieged Gaza Strip.

The Indian navy said it had responded to a request for assistance.

"An aircraft was dispatched and it reached overhead the vessel and established safety of the involved ship and its crew," a navy official told AFP.

"An Indian navy warship has also been dispatched so as to provide assistance as required."