"Fourteen people died and two more were wounded as a result of a state border service helicopter crash," the ex-Soviet republic's frontier guard said in a statement.

It said all of the victims were military servicemen.

The office of Azerbaijan's prosecutor general said later Tuesday that investigators "ruled out external factors" as a possible cause of the crash of the Mi-17 chopper.

"Different versions are being considered, including the pilot's negligence, a technical problem, and climate conditions," it said in a statement.

A black box was recovered at the crash site, the statement added.

Earlier in the day, the country's border service and prosecutor general said in a joint statement that "a military helicopter belonging to Azerbaijan's state border service crashed today at Garakheybat airfield in the Khyzy region at approximately 10:40 am (GMT 0640) while conducting a training flight."

The incident came two weeks after Azerbaijan and Armenia engaged in the worst fighting along their shared border since going to war last year over the contested Nagorno-Karabakh region.

The six-week war claimed more than 6,500 lives and ended in November 2020 with a Russian-brokered ceasefire. The deal saw Yerevan cede swathes of territory that it had controlled for decades.

Six Armenian troops and seven Azerbaijani soldiers were killed on November 16 in a flare-up of tensions. A truce was negotiated the same day by Russian Defence Minister Sergei Shoigu.

Tensions between Baku and Yerevan have been running high since May, when Armenia said Azerbaijan's military crossed its southern frontier to "lay siege" to a lake shared by the two countries.