Taiwan's Presidential Office conducted its first ever tabletop exercise simulating a military escalation with China, several officials briefed on the matter said, at a time when the island is facing renewed Chinese military threats.

Mobile phone footage circulating online appeared to show the Azerbaijani Airlines plane making a steep descent before slamming into the ground in a fireball in western Kazakhstan.

Two passengers and one crew member told Reuters that they heard at least one loud bang as their flight approached its original destination of Grozny in Russia.

Sources told Reuters the plane had been hit by Russian fire. "It was as if it was drunk - not the same plane anymore," one passenger recalled.

The head of Ukraine’s military intelligence (HUR) on Dec. 27 said the aircraft had been hit by “a Russian Pantsir S1 air defense system on Russian terrain.”

A passenger jet operated by Azerbaijan Airlines crashed near the city of Aktau in Kazakhstan on Wednesday, after diverting from an area of southern Russia where Moscow has repeatedly used air defence systems against Ukrainian attack drones.