Officials in Ukraine's northern regions said on Monday (Apr 4) Russian troops there had fully withdrawn or significantly reduced in number, leaving mines and damaged military vehicles behind.
Ukraine has reported Russian troops drawing back or being pushed back in the north since Russia announced last Tuesday that it would scale down its operations there to focus on battles in the east.
The governor of Zhytomyr region, which is west of Kyiv, said no Russian troops remained on its territory.
"They left, leaving some of their vehicles and munitions, but also they left having mined private homes and forests, essentially having left behind a trail of war," Governor Vitaliy Bunechko said in an online post.
Russia's defence ministry has not responded to a request for comment on previous allegations that withdrawing troops are planting mines in civilian areas.
Authorities in the Chernihiv region, northeast of Kyiv, said some Russian troops remained there but had pulled back from around the main city of Chernihiv.
The governor of the neighbouring Sumy region, which lies on Ukraine's border with Russia, said Russian troops no longer occupied any towns or villages in the region and Ukrainian troops were trying to push out units that remained.
Speaking on national television, Sumy Governor Dmytro Zhyvytskyi said Russian troops had abandoned vehicles as they fell back. Some of these were damaged, but others were seized as war trophies by Ukrainian troops, including armoured personnel carriers and tanks, he said.
NATO Secretary-General Jens Stoltenberg said last week that Russian forces were not withdrawing but regrouping, and Ukrainian officials say Russian troops are losing ground rather than retreating of their own accord.