Twelve former Yaroslavl prison officials have been arrested this summer after a video leaked of several men in correctional uniforms and plain clothes beating and waterboarding a prisoner. Russia’s Federal Prison Service (FSIN) vowed to launch a nationwide inspection of correctional facilities and discipline abusive officials after the video’s publication.

A prison in Yaroslavl has become the focal point of torture allegations yet again following the publication of a second video in which guards are seen beating prisoners.

On Thursday, the Novaya Gazeta investigative newspaper published another video showing guards beating prisoners at the same Yaroslavl penal colony. Public Verdict, the rights group that shared the clip with Novaya Gazeta, said it believes the beatings may have been filmed around December 2016.

“This isn’t an isolated case, but only the tip of the iceberg,” Public Verdict said.

“The new video shows us that torture at Penal Colony 1 isn’t an accident but systemic,” Novaya Gazeta wrote.

In the 5-minute video, guards are heard reminding each other to turn off surveillance cameras ahead of beatings, then turn them back on afterward. In the meantime, they are seen lined up in the narrow hallway punching and kicking inmates who are ordered to run back and forth.

Another Novaya Gazeta video shows an inmate demonstrating his bruises to a doctor, while a third brief clip shows an unidentified half-naked prisoner losing consciousness during questioning.

FSIN told Interfax later on Thursday that the videos published by Novaya Gazeta had been uncovered in an internal inspection and had been forwarded to investigators last week.