There has been escalation in Donbas, eastern Ukraine, as the number of Russia-led forces' attacks on Ukrainian positions grew to 21 instances on May 3; proscribed weapons – 120mm and 82mm mortars – were used in nine attacks.

The enemy also opened fire from weapons of infantry fighting vehicles, grenade launchers of various systems, large-caliber machine guns and small arms, the press center of Ukraine's Joint Forces Operation said on Facebook in a morning update on May 4.

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Hot spots were the towns of Avdiyivka and Maryinka, the villages of Novotroyitske, Berezove, Pavlopil, Pyshchevyk, Lebedynske, Mykolaivka, Zolote-4, Novoluhanske, Mayorsk, and Shumy.

"Two members of the Joint Forces have been wounded in shelling," the press center said.

Ukrainian troops fired back in every attack. "According to Joint Forces' intelligence, one invader was killed and another four were wounded on May 3," it said.

Since Saturday midnight, the enemy has already attacked Ukrainian positions near the town of Maryinka in the Skhid (Easter) sector twice, using various types of grenade launchers, larger-caliber machine guns, and small arms. They also shelled Ukrainian troops deployed near the village of Lebedynske, using large-caliber machine guns and small arms.

There have been no Ukrainian army casualties on May 4.