Azerbaijan and its breakaway region of Nagorno-Karabakh have accused each other of violating a cease-fire with intense shelling.
In a statement, the Azerbaijani Foreign Ministry said its army fired at ethnic Armenian-held positions late on March 10 to prevent them from targeting the Azeri town of Aqdam. The ministry claimed 10 to 15 Armenian soldiers were killed and military equipment was destroyed.
Military leaders in Nagorno-Karabakh denied targeting civilians in the Aqdam area and said its fighters had been forced to return fire after a "reconnaissance and subversive" Azeri group tried to penetrate an area under its control.
It said it had sustained no losses despite heavy enemy fire.
Baku and Yerevan have been locked in conflict over Azerbaijan's breakaway region of Nagorno-Karabakh for a quarter-century.
Armenia-backed separatists seized the mainly ethnic Armenian-populated region during a war in the early 1990s that killed some 30,000 people.
International diplomatic efforts to settle the conflict have made little progress.