Govt has provided X category security cover to Aircraft Accident Investigation Bureau DG GVG Yugandhar who is leading the probe into the crash of AI-171. Following a threat perception report, MHA has asked CRPF to provide him cover.Meanwhile, India has granted observer status to an expert from International Civil Aviation Organisation for the crash probe. UN's aviation arm, ICAO had formally requested to send an observer to the inquiry. As a signatory to ICAO's Chicago Convention (1944), India investigates aircraft accidents in accordance with ICAO's and its (Indian) rules.