Armenian soldiers were seen operating a multiple rocket launcher and performing strikes.
Fighting in the disputed region broke out on Sunday when Azeri and ethnic Armenian soldiers exchanged fire. It's been the heaviest clashes in the region since 2016 with dozens of casualties reported. Both sides blame each other for the escalation and report of thousands of casualties.
Earlier Turkish President Recep Tayyip Erdogan pledged to stand by Azerbaijan in the conflict. The Nagorno-Karabakh region is internationally recognised as part of Azerbaijan but has an independent government led by a majority group of ethnic Armenians.