Air India says one of its flights was delayed after a pilot allegedly assaulted a ground engineer on board an aircraft as he prepared to take off for Paris from the southern Indian city of Chennai.

Airline spokesman G.P. Rao says authorities have ordered an inquiry into Saturday's incident, which delayed the flight by an hour with 122 passengers on board.

Rao says the flight departed after another pilot replaced the one involved in the incident, adding that it was not immediately known what triggered the clash.

The Press Trust of India news agency says the engineer, who was in the aircraft for a routine check, suffered a minor chin injury.