The situation in the eastern regions of Ukraine remains complicated and may continue to worsen, the press center of the anti-terrorist operation (ATO) has said.

"The most complex situation remains near the localities of Donetsk, Luhansk, Krasnodon and Popasna, as well as some districts near the border," the press center said on its Facebook account on Tuesday.

A Ukrainian Armed Forces checkpoint, located near the town of Vesela Hora in the Donetsk region, came under Grad rocket strikes at around 0100 last night, it said.

Militants also fired Grad systems against another Ukrainian army checkpoint near the town of Kamysheve, as well as the Luhansk airport at 0400, it said.

Militants are attempting to maintain their control over Horlivka, Avdiyivka, Donetsk, parts of Uspenka, Marynivka and Diakove, the press center said.

Kyiv's Information Resistance group coordinator, Dmytro Tymchuk, for his part, said that Ukrainian troops had taken the town of Dzerzhynsk near Horlivka under their complete control.