New Delhi, July 10 - National carrier Air India Friday grounded a pilot, co-pilot and seven ground employees after they were found guilty of having violated safety norms by allowing three extra passengers on board a fully-loaded Mumbai-Mangalore flight.

'We have de-rostered nine of our employees and have cancelled the licence of the pilot and the co-pilot who have been found involved in the incident. We will take severe action against those found guilty,' said Jitender Bhargava, the carrier's executive director of corporate communications.

The safety breach was discovered by India's airline sector regulator, the Directorate General of Civil Aviation (DGCA), when passengers had to be offloaded May 5 after the aircraft's door got damaged.

A woman was accommodated in the cockpit's jump seat behind the pilots, while two others were made to sit on folding seats meant for cabin crew.

The investigation by the DGCA also proved that boarding passes were prepared manually, which is illegal. The process of ticketing is completely computerised and the system automatically stops generating passes once the flight is full.

According to the security norms, no one is allowed inside the cockpit -- even cabin crews.