Militants of the self-proclaimed Luhansk People's Republic (LNR) are seen at frontline positions located on the troops contact line with Ukrainian forces in the village of Zholobok in Luhansk Region, Ukraine March 23, 2021.

A service member of the Ukrainian armed forces cleans a weapon at fighting positions on the line of separation near the rebel-controlled city of Donetsk, Ukraine April 6, 2021.

A service member of the Ukrainian armed forces walks at fighting positions on the line of separation near the rebel-controlled city of Donetsk, Ukraine April 3, 2021.

A militant of the self-proclaimed Donetsk People's Republic (DNR) uses equipment to observe the area at fighting positions on the line of separation from the Ukrainian armed forces south of the rebel-controlled city of Donetsk, Ukraine April 2, 2021. The upper sign reads: "Watch out. Sniper".

A service member of the Ukrainian armed forces uses binoculars while observing the area at fighting positions on the line of separation near the rebel-controlled city of Donetsk, Ukraine April 3, 2021.

Local resident Roman, 48, is seen at the ruins of his house destroyed during a military conflict between militants of the self-proclaimed Donetsk People's Republic and the Ukrainian armed forces, in Donetsk, Ukraine March 31, 2021.

A militant of the self-proclaimed Donetsk People's Republic (DNR) points a weapon at fighting positions on the line of separation from the Ukrainian armed forces south of the rebel-controlled city of Donetsk, Ukraine April 2, 2021.

A militant of the self-proclaimed Luhansk People's Republic (LNR) is seen at frontline positions located on the troops contact line with Ukrainian forces in the village of Zholobok in Luhansk Region, Ukraine March 23, 2021.

Militants of the self-proclaimed Luhansk People's Republic (LNR) are seen at frontline positions located on the troops contact line with Ukrainian forces in the village of Zholobok in Luhansk Region, Ukraine March 23, 2021.

A militant of the self-proclaimed Donetsk People's Republic (DNR) holds a weapon at fighting positions on the line of separation from the Ukrainian armed forces south of the rebel-controlled city of Donetsk, Ukraine April 2, 2021.

A militant of the self-proclaimed Donetsk People's Republic (DNR) points a weapon at fighting positions on the line of separation from the Ukrainian armed forces south of the rebel-controlled city of Donetsk, Ukraine April 2, 2021.

A service member of the Ukrainian armed forces is seen at fighting positions on the line of separation near the rebel-controlled city of Donetsk, Ukraine April 3, 2021.

A service member of the Ukrainian armed forces cleans a weapon at fighting positions on the line of separation near the rebel-controlled city of Donetsk, Ukraine April 6, 2021.

Militants of the self-proclaimed Luhansk People's Republic (LNR) are seen at frontline positions located on the troops contact line with Ukrainian forces in the village of Zholobok in Luhansk Region, Ukraine March 23, 2021.

A militant of the self-proclaimed Luhansk People's Republic (LNR) is seen at frontline positions located on the troops contact line with Ukrainian forces in the village of Zholobok in Luhansk Region, Ukraine March 23, 2021.

Local resident Angela, 54, grazes goats near her house in the rebel-controlled city of Donetsk, Ukraine March 31, 2021.

A militant of the self-proclaimed Donetsk People's Republic (DNR) stands guard at fighting positions on the line of separation from the Ukrainian armed forces south of the rebel-controlled city of Donetsk, Ukraine April 2, 2021.

A service member of the Ukrainian armed forces stands guard at fighting positions on the line of separation near the rebel-controlled city of Donetsk, Ukraine April 6, 2021.

Local resident Roman, 48, is seen at the ruins of his house destroyed during a military conflict between militants of the self-proclaimed Donetsk People's Republic and the Ukrainian armed forces, in Donetsk, Ukraine March 31, 2021.

A service member of the Ukrainian armed forces reacts at fighting positions on the line of separation near the rebel-controlled city of Donetsk, Ukraine April 6, 2021.

A militant of the self-proclaimed Donetsk People's Republic (DNR) points a weapon at fighting positions on the line of separation from the Ukrainian armed forces south of the rebel-controlled city of Donetsk, Ukraine April 2, 2021.

Militants of the self-proclaimed?Luhansk?People's Republic (LNR) are seen at frontline positions located on the troops contact line with Ukrainian forces in the village of Zholobok in Luhansk Region, Ukraine March 23, 2021.

A service member of the Ukrainian armed forces walks with a weapon at fighting positions on the line of separation near the rebel-controlled city of Donetsk, Ukraine April 6, 2021.

A militant of the self-proclaimed Donetsk People's Republic (DNR) holds a weapon at fighting positions on the line of separation from the Ukrainian armed forces south of the rebel-controlled city of Donetsk, Ukraine April 2, 2021.