The Aircraft Accident Investigation Bureau (AAIB) has found that the pilot-in-command of an August 4 Air India flight from Delhi to Phuket tested non-negative for psychoactive substances in a confirmatory test. The bureau called confirmation of use of a psychoactive substance a serious concern and recommended that India's aviation regulator, the Directorate General of Civil Aviation (DGCA), take appropriate action on priority.

The finding is part of the AAIB's preliminary report on the incident, in which 24 passengers were injured after the aircraft experienced a momentary loss of altitude. The bureau said a detailed investigation into technical and other aspects is continuing.