The Armenian military warned Azerbaijani forces against trying to advance towards Armenia’s border after an Azerbaijani soldier was shot dead there on Sunday.

The soldier, Adil Tatarov, was reportedly killed by Armenian troops guarding the border with Azerbaijan’s Nakhichevan exclave. The Azerbaijani Foreign Ministry accused Yerevan of escalating tensions in the Nagorno-Karabakh conflict zone “instead of holding meetings” with international mediators.

The Armenian Defense Ministry blamed the fatal shooting on “provocative” actions which it said have been taken Azerbaijani troops at some sections of the Armenian-Azerbaijani frontier in recent weeks. The ministry spokesman, Artsrun Hovannisian, said they have been “conducting active engineering works for the purpose of improving and advancing their positions.”

“The armed forces of Armenia have periodically, including in the last several days, warned the commanders of Azerbaijani forces deployed on the border with Armenia that this and other provocative actions cause shootouts and could lead to undesirable losses,” Hovannisian wrote on Facebook. Such actions “cannot stay unanswered,” he said.

Armenia’s newly appointed Defense Minister Davit Tonoyan and Foreign Minister Zohrab Mnatsakanian jointly visited some of the Armenian army posts on the Nakhichevan border on May 18. According to his press office, Tonoyan told troops serving there to “strictly thwart any adventure by the enemy.”

The two ministers inspected the troops two days after Azerbaijan’s President Ilham Aliyev visited Nakhichevan and touted an Azerbaijani military buildup carried out there in recent years. “Long-range missiles deployed in Nakhichevan can destroy any military target of the enemy,” Aliyev said.

Armenia’s capital Yerevan is located roughly 70 kilometers northwest of the nearest section of the Nakhichevan border.