Three Armenian soldiers were killed in an exchange of gunfire with Azerbaijani forces, the Armenian Defence Ministry said on Wednesday, the latest military incident between the countries since their war over the disputed region of Nagorno-Karabakh.
Both Azerbaijan and Armenia have reported occasional gun battles in recent months along their shared border, sparking fears of a flare-up in the territorial dispute.
An Azerbaijani soldier died and three Armenian troops were wounded on Friday.
“Armenian armed forces opened fire at Azerbaijani army positions at the Kelbajar sector of the Armenian-Azerbaijani state border,” the Azerbaijani Defence Ministry said.
But Armenia blamed the Azerbaijani military for initiating the incident.
"Three Armenian servicemen were wounded in the intense shoot-out," it said.
The clashes continued late into the evening, both countries reported.
The six-week war last autumn claimed about 6,500 lives and ended in November with a Russian-brokered ceasefire under which Armenia ceded territory it had controlled for decades.
Tensions between Baku and Yerevan have been running high since May, when Armenia accused Azerbaijan's military of crossing its southern frontier to “lay siege” to a lake shared by the two countries.
“This is our ancestors' land, we are on our land,” Azerbaijani President Ilham Aliyev told the AzTV network on Thursday, referring to the territory which Armenia considers part of its Syunik district.
In May, Mr Aliyev said Baku was ready for peace talks with Armenia.
Ethnic Armenian separatists in Nagorno-Karabakh broke away from Azerbaijan as the Soviet Union collapsed, and the ensuing conflict has claimed about 30,000 lives.