Most of the off-loaded passengers stood in line for almost an hour before being told that the flight was full even before they could reach the check-in counters. This raised tempers, said sources.

According to an airport official, offloading is fairly common during the peak season on international flights since most airlines overbook by around 10 per cent of their flight capacity.

“Unlike domestic flights, there are no cancellation charges nor is there a penalty if a passenger does not turn up so airlines generally tend to overbook since last minute drop-outs are common,” the official said.

However, he added, during peak season the airlines risk the possibility of all those who have booked their tickets on a particular flight turning up, which he said was the case with the AI 125 Mumbai-London-Chicago slated to take off at 9 am.