For the second time in a few months, prisoners apparently linked to ISIS have taken a group hostage in a Russian prison amid reports of casualties.

On Friday, Russian prisoners took employees hostage in a prison in the Volgograd region (south), according to authorities who reported at least four wounded.

The Federal Prison Service said in a statement that "convicts have detained employees of the IK-19 Correctional Facility. Measures are currently being taken to free the hostages, and there are injuries."

While the governor of the region, Andrei Bocharov, announced on the Telegram application that four prison service employees were injured in the attack and were taken to the hospital.

During a meeting of the Russian Security Council during which the hostage-taking process was discussed, President Vladimir Putin requested a report from Interior Minister Vladimir Kolokoltsev.

The prison, which applies a “harsh regime” - strict detention conditions - is located in the city of Surovikino, about 120 kilometers west of Volgograd, the capital of the region.

Video clips

Video clips, the authenticity of which was not confirmed by Agence France-Presse, suggest the theory of premeditated hostage-taking by sympathizers of the terrorist organization ISIS.

The first video broadcast by Russian media shows a room with a blood-stained floor.

The video appears to show about four prison guards being detained, some of them bloody, along with at least two other men standing with a third person speaking Arabic.

Then the latter announces in Russian his affiliation with ISIS.

In the video - which lasts 46 seconds - one of the men holds a knife by the neck and the other hand holds a guard by the neck.

Another video clip shows four attackers, including at least two carrying a knife, and one of them raising what appears to be an ISIS flag.

The governor of the Volgograd region, Andrei Botcharov, wrote on Telegram, “Every person present on our territory is obliged to respect and observe the laws of Russia.”

He added, "We will not allow anyone to try to stir up ethnic strife," stressing that "there is enough equipment to help the victims."

Previous attacks

Last June, a number of ISIS members detained two guards in a prison in the Rostov region, located in the south.

Russian special forces were able to kill the two hostage takers and free the two guards hours after the crisis.

Russia has repeatedly been subjected to attacks for which ISIS claimed responsibility, although the organization's influence in the country is limited.

This comes after the killing of 145 people in March in an attack by ISIS members on a concert hall in Moscow, the deadliest terrorist attack in terms of death toll in Russia in two decades.

ISIS has repeatedly threatened to launch attacks on Russia because of its support for the Syrian government, according to Agence France-Presse.