Spokesman for Ukraine's Defense Ministry Dmytro Hutsuliak has said Russian-led forces are improving the airspace surveillance system in Donbas to identify unmanned aerial vehicles of the OSCE Special Monitoring Mission to Ukraine.

"The command of the Russian armed forces are taking measures to increase the level of concealment of the use of forces and means of units of the 1st (Donetsk) and 2nd (Luhansk) Army Corps," he told a briefing with reference to the data of the Main Intelligence Directorate.

According to Hutsuliak, the enemy has enhanced the system for monitoring airspace and alerting unit commanders about the use of unmanned aerial vehicles of the OSCE mission to urgently strengthen the camouflage regime, ceasefire, and limit the movement of weapons and military equipment.

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Thus, the enemy is trying to conceal the facts of shelling of Joint Forces' positions and provoking Ukrainian soldiers to return fire, to discredit them.

"The units of the Joint Forces are ready for insidious hostilities in the area of rebuffing and deterring the armed aggression of the Russian Federation in the east of our state," the officer said.