“Urban warfare in Debaltsevo is continuing. Several groups totaling around 120 servicemen surrendered, after finding our units had taken part of the city,” the source said.
A Kiev military spokesman said earlier on Tuesday that the information was unconfirmed.
The town of Debaltsevo, located between Ukraine’s two breakaway regions of Donetsk and Luhansk, has in recent weeks become a hot spot for heavy fighting between Kiev-led troops and local militia.
Thousands of Ukrainian servicemen are reportedly surrounded in the town, and civilians are being evacuated from the area.
On Monday, Kiev said that Debaltsevo remains the only area where fighting has not subsided after a new ceasefire agreement came into effect on Sunday.
The ceasefire deal was agreed on during talks between the leaders of Ukraine, Russia, France and Germany last week, after a previous truce deal, signed between Ukraine’s warring sides in September last year, had been routinely broken.