Reports of repeated incidents along Armenia-Azerbaijan border causes grave concern, OSCE Chairperson in Office, Swiss Foreign Minister Ann Linde said in a Twitter post.

“Urge sides to build on recent humanitarian steps and implement November 9 statement in full to address unresolved issues peacefully,” she added.

Three Armenian servicemen were killed, four were wounded as Azerbaijan undertook an offence in the Gegharkunik section of the Armenian-Azerbaijani line of contact.

A number of Azerbaijani UAVs have been spotted trying to enter the Armenian airspace over the past two days. An Aerostar drone was downed near Vardenis late on Thursday.