Russian officials say four police officers in Siberia's Kemerovo Oblast have been arrested and charged with abuse of power and violent conduct that allegedly led to a detainee's death.
The four were detained on March 25 for their alleged involvement in the torture of a suspect with a gas mask in September.
The detainee is reported to have died during the interrogation.
On March 28, the authorities filed similar charges against two former police officers in Kemerovo over the death of a different suspect.
The Kemerovo announcements come amid a wave of fresh concern about police brutality in Russia
The protests were sparked after police in the central republic of Tatarstan this month allegedly raped a detainee with a bottle
That detainee later died in a hospital.
Based on reporting by Interfax and ITAR-TASS