(AAIB) has released its preliminary report into the fatal Boeing 787-8 plane crash on June 12 that killed 260 people. The report has found that the fuel supply to both engines of Air India flight AI171 was cut off within a second of each other, causing confusion in the cockpit and the airplane plummeting back to ground almost immediately after taking off.

The 15-page report says that in the cockpit voice recording, one unidentified pilot asked the other why he had cut off the fuel, which the other denied.

"The tone and direction of the investigation suggest a bias towards pilot error... ALPA India categorically rejects this presumption and insists on a fair, fact-based inquiry," Airline Pilots' Association of India (ALPA) said in a statement.

The association has also demanded that its representatives should be observers in the investigation process to ensure transparency and accountability.

ALPA Indiais a member associate of the International Federation of Airline Pilots' Association (IFALPA).