Donbas militants mounted an attack on Ukrainian positions near the village of Zaitseve close to the occupied town of Horlivka, Donetsk region, in the Anti-Terrorist Operation zone in the early hours of Monday, using 120mm and 150mm weapons, military journalist Roman Bochkala, who is now in the ATO zone, has reported.

"The General Staff has confirmed. There was a direct hit of the position of the 53rd brigade between the village of Zaitseve and Mayorsk at 03.00 in the morning today. Our casualties are four killed in action and three wounded in action," Bochkala wrote on Facebook.

He also added that the situation near Zaitseve had notably aggravated, as the Ukrainian side sustains casualties every day.

Interfax-Ukraine has not obtained confirmation of this report from the ATO Headquarters yet.