A fire killed 15 servicemen and seriously injured three others in Armenia on Thursday after ripping through a military barracks overnight, the defence ministry said.
The blaze "broke out in the barracks of an engineer and sniper company of a military unit", the ministry said.
"Fifteen servicemen were killed as a result... The condition of three (other) servicemen is assessed as serious."
It said the fire started at around 01:30 am on Thursday (2130 GMT Wednesday) in the barracks in Azat, a village in the eastern region of Gegharkunik, near the border with Azerbaijan.
The incident was "a result of the violation of fire safety rules, during which prohibited substances were used", Defence Minister Suren Papikyan told a cabinet meeting, citing preliminary information.
"We are talking about gasoline," he said.
Papikyan dismissed an army corps commander and several senior officers over the incident.
Investigators said a criminal probe was underway into the violation of safety standards.
In August 2022, more than a dozen people were killed in an explosion and subsequent fire at a busy market in Armenia's capital Yerevan.
The Caucasian nation of around three million people is still recovering from a 2020 war with Azerbaijan, which ended in a heavy defeat and sparked a political crisis.
Despite the end of the large-scale fighting, tensions persist between the former Soviet rivals over their borders.
On Thursday, Armenia's defence ministry said one of its servicemen was wounded by Azerbaijani fire and is in "serious" condition
In a comment to local media, Azerbaijan's defence ministry denied that its soldiers opened fire.
Both sides accuse each other of violating a fragile truce that was struck under Russian mediation to end fighting in 2020.