Azerbaijan on Thursday observed a nationwide day of mourning for the victims of the plane crash that killed 38 people and left all 29 survivors injured as speculation mounted about a possible cause of the disaster,

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.

An Azerbaijan Airlines flight that crashed in Kazakhstan on Christmas Day was downed by a Russian air defence system, a preliminary investigation has found, according to reports.