Story highlights The plane took off from Chennai at 8:30 a.m. local time

It was scheduled to land three hours later

New Delhi, India (CNN) An Indian Air Force plane carrying 29 people went missing Friday morning during what was supposed to be a flight to an archipelago in the Indian Ocean, India's military said.

A search was underway for the Antonov AN-32 transport plane, which took off from Chennai at 8:30 a.m. local time and was scheduled to land three hours later at Port Blair, in India's Andaman and Nicobar Islands, said Cmdr. Anupam Banerjee, spokesman for the Indian Air Force.

Air force, navy and coast guard crews were searching for the plane. Details on who was aboard the plane weren't immediately available.

Port Blair is the capital of the Andaman and Nicobar Islands, an Indian territory consisting of more than 500 islands -- only three dozen of which are inhabited -- in the Indian Ocean, hundreds of kilometers east of the Indian subcontinent.

Port Blair's airport is an Indian naval facility that also is used by civil aircraft.