Mumbai, Aug. 14 -- Union road transport minister Nitin Gadkari and 158 other passengers were held up at Nagpur for nearly six hours after a Delhi-bound IndiGo flight returned to bay on Tuesday following a "caution message" the pilot observed during engine start-up.

The aircraft returned to bay for requisite checks after the pilot observed a "momentary caution message", the airline said. All passengers were deboarded and taken back to the airport terminal building. "The caution message reappeared during ground checks. The aircraft was withdrawn from service and is under maintenance at Nagpur," IndiGo said in a statement.

An airport official said flight 6E-636, using another aircraft, took off from Nagpur for Delhi at 1.54 pm, carrying "mos...