Overnight combat operations by Azerbaijan in Aghdara, Fuzuli-Jabrayil and Gubadli continue as Azerbaijani and Armenian foreign ministers hold talks in Moscow.
The Azerbaijani army's operations to recapture territories occupied for nearly 30 years by Armenian forces are continuing as the two sides engage in the deadliest clashes since the 90s.
Azerbaijani authorities said advances continued on Wednesday in Upper Karabakh, or Nagorno-Karabakh, Azerbaijan's territory under the occupation of Armenians since 1991. The persistent fighting comes after a second ceasefire, brokered by Russia, failed to hold.
Overnight combat operations in Aghdara, Fuzuli-Jabrayil and Gubadli continued with varying intensity, while Armenian forces fired at Azerbaijani positions using small arms, mortars, and howitzers, according to Azerbaijan's Defence Ministry.
Russian Foreign Minister Sergey Lavrov held two separate meetings with his Armenian and Azerbaijani counterparts in Moscow on Wednesday to discuss the implementation of a ceasefire in Nagorno-Karabakh.
"During the talks, urgent issues related to the implementation of previously reached agreements on a cease-fire in the Nagorno-Karabakh conflict zone and the creation of conditions for its sustainable settlement were discussed," the ministry said in a statement, following Lavrov's meeting with Armenia's Zohrab Mnatsakanyan and Azerbaijan's Jeyhun Bayramov.
The pair are due to meet with the US Secretary of State Mike Pompeo on Friday.
They have ruled out a trilateral meeting and will meet Pompeo separately.
Armenia's Prime Minister Nikol Vovayi Pashinyan said on Wednesday their side will continue to fight until an acceptable diplomatic solution is found
Units of the 18th motorised rifle division of the Armenian Armed Forces in Jabrayil and Gubadli were forced to retreat, the statement said.
"The regiment's chief of artillery, commander of artillery division, and commander of the 4th battalion together with the battalion's military personnel were destroyed."
Noting casualties among Armenian units in the 6th and 7th mountain rifle regiments, the ministry said that Vahan Sargsyan, deputy commander of the regiment, was among those killed.
Troops of the Azerbaijan Armed Forces control the operational situation along the entire front, it said.
In a separate statement, the ministry also said that starting this morning, Armenian forces were shelling the western city of Tartar and regional territory using artillery.
Since fresh clashes erupted on September 27, Armenia forces launched at least two missile attacks on Ganja, Azerbaijan's second-largest city, far from the front line. The attacks killed some two dozen civilians, including children, and injured scores more.
On Thursday, Armenia targeted civilians at a cemetery in the western city of Tartar, killing four and injuring four others.
Baku has reported 63 civilian casualties following Armenia's shelling on civilian settlements but has yet to disclose military losses.
Armenian forces in occupied-Karabakh say 772 soldiers and 36 civilians have been killed in the flare-up of fighting.
Upper Karabakh conflict
Relations between the two former Soviet republics have been tense since 1991, when the Armenian military occupied Nagorno-Karabakh.
Four UN Security Council resolutions and two from the UN General Assembly, as well as international organisations, demand the “immediate complete and unconditional withdrawal of the occupying forces” from occupied Azerbaijani territory.
In total, about 20 percent of Azerbaijan's territory – including Nagorno-Karabakh and seven adjacent regions – has been under illegal Armenian occupation for nearly three decades.
The Organization for Security and Co-operation in Europe Minsk Group – co-chaired by France, Russia, and the US – was formed in 1992 to find a peaceful solution to the conflict, but to no avail. A ceasefire, however, was agreed to in 1994.
World powers, including Russia, France, and the US, have called for a new ceasefire. Turkey, meanwhile, has supported Baku's right to self-defence and demanded the withdrawal of Armenia's occupying forces.