Russia-Ukraine updates: Putin suspends key US-Russia nuclear treaty in speech denouncing West

The village of Hrekivka in Ukraine's Luhansk region has been liberated, its governor, Serhiy Haidai, said Friday, adding that fierce fighting continues for other settlements.

"I’ve seen some soldiers already posted a photo of them standing on the background of the sign 'Hrekivka,' so its not a secret anymore — it is already liberated. And we keep moving in that direction," Haidai said.

"After liberating Lyman [in Donetsk at the end of last month], as expected, the main battles are on the direction of Kreminna. The occupiers are pulling their main forces there. This is where the beginning of de-occupation of Luhansk oblast lies," Haidai said.

He added, "Luhansk region liberation will be tougher than Kharkiv region. All those Russian military who ran from Kharkiv region and Lyman ran to our direction, so the occupation forces increased in number."

-ABC News' Will Gretsky

Russian forces struck a residential neighborhood in the southeastern city of Zaporizhzhia early on Thursday, officials said.

Ukrainian officials released images they claim show evidence of tortures and killings in eastern Kharkiv, in areas recently reclaimed from Russia.

Authorities are investigating an alleged Russian torture chamber in the village of Pisky-Radkivski, according to Serhiy Bolvinov, the head of the investigative department of the national police in the region.

Bolvinov posted an image of a box of what appeared to be precious metal teeth and dentures presumably extracted from those held at the site.

Andriy Kostin, Ukraine's prosecutor general, also spoke of new evidence of torture and killings found Wednesday in the Kharkiv region.

Kostin told The Associated Press on the sidelines of a security conference in Warsaw that he had just been notified of four bodies found with signs of possible torture. He said they were believed to be civilians but an investigation was still needed.

Two bodies were found in a factory in Kupiansk with their hands bound behind their backs, while two others were found in Novoplatonivka, their hands linked by handcuffs.

During his public speech, Kostin said officials found the bodies of 24 civilians, including 13 children and one pregnant woman, who had been killed in six cars near Kupiansk. It is not clear when the discovery was made.

-ABC News' Jason Volack

Ukrainian forces continue "to make progress" in counteroffensive efforts against Russian troops along both the northeastern and southern fronts, the U.K. Ministry of Defense said Wednesday in an intelligence update.

In the northeastern Kharkiv region, according to the ministry, Ukrainian forces have "now consolidated a substantial area of territory east of the Oskil River," advancing up to 20 kilometres "beyond the river into Russia's defensive zone towards the supply node of the town of Svatove."

"It is highly likely that Ukraine can now strike the key Svatove-Kremina road with most of its artillery systems, further straining Russia's ability to resupply its units in the east," the ministry said. "Politically, Russian leaders will highly likely be concerned that leading Ukrainian units are now approaching the borders of Luhansk Oblast, which Russia claimed to have formally annexed last Friday."