NEW DELHI, India—An Air India pilot and a cabin crew member are being investigated after an argument over a lunch box delayed a flight by more than 2 hours, an official said Wednesday.

Passengers had already boarded Monday's flight from Bangalore to Kolkata when the purser refused to wash the box containing food that the pilot had brought from home.

In full view of passengers, they nearly came to blows before other crew members intervened and both men were taken off the aircraft.

They have now been grounded and are being investigated.

Media reports said cabin crew often complain about haughty pilots demanding special service.