Ukrainian officials claim to have unearthed a “torture chamber” used by Russian troops, as yet more civilian bodies were discovered in recently liberated portions of the Kharkiv province.

The grisly news came as Russia’s president Vladimir Putin said he’d finalized his so-called annexation of a fifth of Ukraine.

The under-siege nation’s defense ministry on Tuesday compared harrowing scenes found in the newly liberated village of Pisky-Radkivski to “a mini Auschwitz.”

The ministry shared disturbing images, including some pictures of an abandoned gas mask supposedly “put on the head of a victim who was covered with a smoldering rag and buried alive.”

Another image showed a plastic container with seemingly dozens of “gold dental crowns” pulled from victims.

It was found along with a sex toy that Russian troops used on villagers and captured Ukrainian forces in the “terrible torture chamber,” according to local National Security Service investigations chief Sergiy Bolvinov.

“Neighbors constantly heard screams from there,” insisted Bolvinov, who said wires and ropes were also found in the basement of the village about 100 miles outside the city of Kharkiv.

“The police are well aware of the torture of being buried alive and the use of a gas mask with a smoldering rag,” he said, without detailing how many people are thought to have been tortured and killed there.

He shared a video of officers looking around the squalid basement, where lines of blood appear to be scratched into walls. “These are the conditions in which they were being held … They were tortured here,” one of the men can be heard saying.

The National Police of Ukraine also highlighted the find as “another torture chamber of the Russian occupiers.”

“After the de-occupation, our police officers document here the war crimes … locals were kept in inhumane conditions. People were intimidated, beaten and abused,” the service said.

Pisky-Radkivski, on the east bank of the Oskil river and on the southeast corner of the Kharkiv province, is among the most recently liberated villages in northern Ukraine.

Similar tales of torture have greeted Ukrainian forces as they’ve fought their way through the province in recent weeks.

Ukraine’s prosecutor general, Andriy Kostin — who was at a security conference in the Polish capital of Warsaw Wednesday — told reporters that four dead bodies had been found elsewhere in the province with signs of torture and extrajudicial killing.

Two bodies were found in a factory in Kupiansk, 30 miles up rover from Pisky-Radkivski, with their hands bound behind their backs, Kostin said.

Ukrainian forces near the city had also found 24 civilians dead in their cars, including 13 children and one pregnant woman, the prosecutor added.

In another village on the banks of the Oskil — Novoplatonivka, two more bodies were found shackled, he said.

The Ukrainian national police also highlighted a police station in another Kharkiv village, Velikiy Burluk, “which the occupiers turned into their fortified base and a torture chamber for local residents.”

“The Russians were based here, illegally detaining and abusing local residents,” the National Police force said.

The Kremlin has repeatedly denied human-rights abuses or attacks on civilians despite overwhelming evidence to the contrary.

The terrible tally came as Putin put the finishing touches on his provincial putsch, claiming Donetsk, Luhansk, Kherson and Zaporizhzhia regions as his own.

The Russian leader signed the final paperwork to declare the four Ukrainian provinces — none of which are fully under Russian control — as integral parts of Russia.

The annexations, which have been roundly denounced as illegal and baseless by the international community, come after a series of sham referendums held essentially at gunpoint.

Putin called the results — which Russia unsurprisingly favored annexation by a landslide — “more than convincing” Wednesday, adding that the process was “absolutely transparent and not subject to any doubt.”

“This is objective data on people’s mood,” Putin said of the ballots collected by armed soldiers from the relatively few civilians not yet displaced by the seven-month war.

Putin added that he was happily “surprised” by the results.

“The Russians were based here, illegally detaining and abusing local residents,” the National Police force said.

Despite overwhelming evidence, the Kremlin has repeatedly denied human-rights abuses or attacks on civilians in its so-called “special military operation” in Ukraine.