Nagorno-Karabakh's military on August 1 accused Azerbaijani forces of launching attacks on its positions in the territory’s north and northwest.
The Karabakh Defense Army said that throughout the day its troops thwarted Azerbaijani "attempts to cross the line of contact."
"The Armenian side suffered no casualties," it said in a statement issued in the evening. "The situation remains tense."
The statement added that Russian peacekeeping forces stationed in Karabakh received "detailed information" about the situation on the front line.
A Karabakh lawmaker, Artur Harutiunian, told RFE/RL’s Armenian Service shortly afterward that the fighting had stopped. He also said that the Azerbaijani Army did not capture any Karabakh Armenian positions.
"Everything is under the control of our armed forces," Davit Babayan, the Karabakh foreign minister said.
The Azerbaijani Defense Ministry categorically denied any cease-fire violations in or around Karabakh.
The situation along the Karabakh line of contact had been relatively calm since March.
Earlier in the evening, Arayik Harutiunian, the Karabakh president, held what appeared to be an emergency meeting with Defense Army commander Kamo Vartanian and other security officials.
Meanwhile, Armenian Foreign Minister Ararat Mirzoyan held a phone call with U.S. Assistant Secretary of State Karen Donfried. An Armenian readout of the call made no explicit mention on the reported escalation in Karabakh.
Donfried spoke last month with Mirzoyan and Azerbaijani Foreign Minister Jeyhun Bayramov the day after their direct talks held in Tbilisi. A week later, U.S. Secretary of State Antony Blinken phoned the leaders of Armenia and Azerbaijan. Blinken tweeted afterward that he saw a "historic opportunity to achieve peace in the region."
The Armenian side said last week that Azerbaijani forces opened fire at two villages in Nagorno-Karabakh and on Armenian Army positions on Armenia’s border with Azerbaijan. Baku denied the accusations.
Azerbaijani Defense Minister Zakir Hasanov on July 30 ordered his troops to be ready to "prevent provocation attempts by the enemy with decisive measures." Some commentators in Yerevan suggested that Baku is preparing the ground for another escalation in the conflict zone.