This photo shows the wreckage of an unknown drone which crashed on the outskirts of Upper Uzunteppe village, Ardabil Province, northwestern Iran, on October 13, 2020. (Photo by IRNA)

An unidentified unmanned aerial vehicle has crashed in Iran�s northwestern province of Ardabil as intense fighting continues between neighboring Armenia and the Republic of Azerbaijan over the disputed Nagorno-Karabakh region despite a Russian-brokered ceasefire clinched last week.

Deputy Governor of Ardabil Province Behrouz Nedaei told IRNA that the drone went down on the outskirts of Upper Uzunteppe village of Parsabad County on Tuesday.

Nedaei added that investigations are underway to determine the origin of the aircraft, noting that the crash did not cause any damage at the site.

IRNA, however, said local authorities believe the drone possibly belongs to one of the two neighbors involved in fighting over the Nagorno-Karabakh region.

Earlier this month, northwestern Iranian border regions had, on several occasions, been hit accidentally by mortar shells and rockets exchanged between the armies of Armenia and Azerbaijan.

Those incidents prompted stern warnings from senior Iranian officials, with Defense Minister Brigadier General Amir Hatami pledging stronger measures than warnings if such incidents keep happening.

Tehran has, at the same time, offered to mediate in the conflict, calling on both sides to exercise restraint, end the conflict immediately and resume negotiations.

Since late September, Armenia and Azerbaijan have been engaged in bitter clashes over Nagorno-Karabakh, a breakaway region of Azerbaijan controlled by Armenians after a 1990s war.

Nearly 600 people, including 67 civilians, have been killed in the latest fighting since last month, according to a tally based on tolls given by both sides.

The warring sides reached a humanitarian ceasefire on Saturday following 11 hours of Russia-mediated talks in Moscow, but the agreement has failed to end the clashes.

The new clashes have made a mockery of the truce deal, with the two Caucasus rivals accusing each other of serious violations and crimes against civilians.

On Monday, Russia urged Armenia and Azerbaijan to immediately start observing the humanitarian truce, which was meant to halt fighting to allow both sides to exchange prisoners and the bodies of people killed.