Russian-led forces have mounted two attacks on Ukrainian army positions in Donbas since Sunday midnight.
"The armed forces of the Russian Federation and its mercenaries have violated the ceasefire twice since the beginning of the current day, October 20," the press center of Ukraine's Joint Forces Operation (JFO) said in an evening update posted on Facebook.
The enemy opened fire from automatic grenade launchers, heavy machine guns and small arms, the report said.
Both attacks were reported in the area of responsibility of the Pivnich (North) sector near Zolote-4 and outside the village of Orikhove.
According to the update, there have been no casualties among the Ukrainian military since Sunday midnight.
"The units of the Joint Forces adhere to the ceasefire and are ready for any insidious and provocative actions of the enemy," the press center added.