Azerbaijan’s leader on Monday accused Moscow of carrying out a “cover up” over a passenger jet crash last month that claimed 38 lives, as relations sour between the two neighbors.

Russian President Vladimir Putin apologized for the “tragic incident,” which left 38 people dead, though he stopped short of taking responsibility.

Azerbaijan President Ilham Aliyev said Russia is behind the Christmas Day crash of an Azerbaijan Airlines plane in Kazakhstan, which killed 38 of the 67 people aboard. The motives of the incident remain unclear.

Azerbaijan’s President Ilham Aliyev has accused Russia of accidentally shooting down an airliner on Christmas Day in a disaster that killed 38 people, and covering up the cause.

Azerbaijani President Ilham Aliyev on Sunday demanded that Russia admit that it fired at an Azerbaijan Airlines passenger jet before it crashed, accusing Moscow of initially trying to cover up the cause of the fatal disaster.

Azerbaijani President Ilham Aliyev says Russia shot down one of his country's passenger planes "by accident" last week.

Azerbaijani leader Ilham Aliyev is demanding answers, saying Vladimir Putin's latest apology "isn't enough" and that Moscow must take responsibility.

In the crash’s aftermath, Azerbaijan has unleashed rare and stinging criticism of Russia, with the country’s president saying Moscow’s response has caused “surprise, regret and rightful indignation.”