Azerbaijan and Armenia accused each other of shelling military positions and villages on Thursday, breaking a day of ceasefire in border clashes between the two former Soviet republics.
Eleven Azeri soldiers and a civilian, and four Armenian servicemen, have died since Sunday in renewed conflict between countries who fought a 1990s war in the mountainous Nagorno-Karabakh region.
International concern is heightened because of the threat to stability in a region serving as a corridor for pipelines taking oil and gas from the Caspian Sea to global markets.
Both countries' defense ministries accused the other of firing mortars from before dawn and encroaching on territory, though there were no casualties reported.
It was "the first serious violation of the fragile ceasefire established yesterday," the Armenian ministry said.
The neighbors have long been in conflict over Azerbaijan's breakaway, mainly ethnic Armenian region of Nagorno-Karabakh. But the latest flareups are around the Tavush region in northeast Armenia, some 300 km (190 miles) from the enclave.
Ethnic Armenians in Nagorno-Karabakh declared independence during a conflict that broke out as the Soviet Union collapsed in 1991. Though a ceasefire was agreed in 1994, Azerbaijan and Armenia frequently accuse each other of attacks around Nagorno-Karabakh and along the separate Azeri-Armenian frontier.
