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

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.

Azerbaijani President Ilham Aliyev blasted Russia for putting forward “absurd” theories initially and said Moscow must compensate victims’ families.

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.

Vladimir Putin apologized Saturday after the US and Azerbaijan accused Russia of shooting down a passenger plane, killing 38 people.

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.”

Russia's federal air transport regulator states that the Azerbaijan Airlines Embraer 190 which crashed after diverting to Aktau had made two unsuccessful attempts to land at Grozny, the flight's original destination.

Two U.S. military officials told NBC News that they had intelligence indicating that Russians may have misidentified the plane and shot it down.

Chechen leader Ramzan Kadyrov is believed to be sheltering two men linked to plots to assassinate two Uzbekistani officials last year, according to an Uzbek source personally familiar with the situation who spoke to The Moscow Times on condition of anonymity for fear of reprisal.

Europe’s air transport safety regulator has expanded its conflict-zone advisory for Russian airspace, following the crash of an Azerbaijani airliner damaged by military activity in Chechnya.

The EU's aviation safety watchdog on Jan. 9 issued a new alert advising non-European airlines to avoid flying over western Russia following the downing of an Azerbaijan Airlines plane last month. The crash, which killed 38 people, is believed to have been caused by Russian air defenses firing at Ukrainian drones.