Ukraine said Monday that it had identified four locations where Russian forces tortured detainees in Kherson before Moscow withdrew troops from the southern Ukrainian city.

Since the Russian army withdrew on November 11 after occupying the city for eight months, Kyiv has accused Moscow's forces of perpetrating abuses on a "horrific" scale.

The Office of the General Prosecutor said officials had inspected "four premises" where Russian troops "illegally detained people and brutally tortured them."

Russian forces set up "pseudo-law enforcement agencies" in Kherson detention centres as well as in a police station, it said in a statement.

Parts of rubber truncheons, a wooden bat, an incandescent lamp and "a device with which the occupiers tortured civilians with electricity" were found, prosecutors said.

"Law enforcement officers continue to collect evidence" of what Ukrainian officials said were "crimes" carried out by the Russian military, the statement added.

Russian authorities also left behind paperwork documenting the administration of the detention sites, the prosecutor's statement added.

Last week Ukrainian ombudsman Dmytro Lubynets described as "horrific" the scale of torture discovered in Kherson.

AFP spoke last week to a Kherson resident who said he spent weeks in detention where he was beaten and electrocuted by Russian and pro-Russian forces.