Experts say evidence in the Azerbaijan Airlines plane crash in Kazakhstan points to a possible midair explosion, not an encounter with a flock of birds.

Azerbaijan Airlines’ Embraer 190 was en route from Baku to the Russian city of Grozny when it was diverted for reasons yet unclear and crashed while making an attempt to land in Aktau in Kazakhstan.

Azerbaijan Airlines said on Friday that preliminary results showed that one of its planes which crashed in Kazakhstan on Wednesday experienced "external physical and technical interference".