Inmates at a prison in southern Russia’s Volgograd region seized control of the facility and took hostages on Friday, with at least three prison guards killed and all four attackers "neutralized" by special forces, officials said.The siege comes two months after Islamic State-linked prisoners took guards hostage in another facility and as ethnic tensions run high following a deadly ISIS-claimed Moscow concert hall attack.Here is everything we know about the hostage situation:What do we know about the attack?The inmate uprising took place at the IK-19 Surovikino penal colony located around 120 kilometers west of the region’s capital city Volgograd.

The colony can hold over 1,200 prisoners.The Federal Penitentiary Service (FSIN) said in a statement that “convicts took employees of the (IK-19) correctional institution hostage. FSIN said later in a statement that “four criminals took eight prison staff members and four inmates hostage” and confirmed that all four attackers had been killed.At least three prison employees died following the attack.

Several guards and inmates were injured.The incident took place during a meeting of the prison's disciplinary commission, FSIN said.Footage circulated on social media appeared to show inmates at the penal colony standing above bloodied prison guards.In another video, a prison guard covered in blood is seen apparently being forced to ask President Vladimir Putin “to fulfill the [attackers’] demands” and saying that he needed medical help.“Your own people have abandoned you, they don't help,” said the man who appears to be recording the video.The Moscow Times could not verify those images.At least four prison staff were hospitalized following the attack, according to Volgograd Governor Andrei Bocharov.“An operational headquarters has been set up to coordinate work on releasing the hostages.

Law enforcement and security agencies are carrying out operational activities.

There is no threat to the civilian population,” Bocharov added.Putin said he had been informed about the hostage siege. Several hours after the hostage crisis first started, the state-run TASS news agency reported that the prison was under the control of security forces and the siege had ended.What do we know about the attackers?TASS said that at least four prisoners were involved in the hostage-taking.

Three were convicted of drug trafficking and another was convicted of manslaughter during a fight.Governor Bocharov did not comment on the identity of the hostage-takers but alluded to reports they were citizens of Central Asian countries.“Everyone on our territory is obliged to respect and comply with the laws of Russia.

We will not allow anyone to try to incite ethnic discord,” he said in a statement published by the regional administration.Unverified footage circulated online showed the hostage-takers shouting “Allahu Akbar” and holding knives and flags that resemble that of ISIS.“Law enforcement officers have been captured.

Those who oppressed, humiliated and tortured Muslims have been killed…We treated them in a similar way.

No mercy,” a man could be heard saying off-camera in one video.Unconfirmed reports said that the attack was allegedly carried out for “Muslim brothers” and as apparent revenge for the arrested terrorists who attacked a Moscow concert hall in March.

The Moscow Times could not independently verify these reports.Previous attacks this yearIn June, prisoners aligned with ISIS staged a similar siege at a jail in the southern Rostov region.

During that incident, Russian special forces killed the hostage-takers and freed the guards following a stand-off.Inter-ethnic tensions are running high in Russia following the March attack on Moscow's Crocus City Hall concert venue that killed 145 people — the deadliest terror attack in Russia in two decades.A Central Asian branch of ISIS claimed responsibility for the Crocus City Hall attack and the four suspected gunmen, now in pre-trial detention, are citizens of Tajikistan.In June, at least 21 people were killed in coordinated terrorist attacks in Derbent and Makhachkala, the two largest cities in the North Caucasus republic of Dagestan.

Two synagogues, two Eastern Orthodox churches, and a police post were simultaneously attacked by armed men, killing 16 policemen and at least five others, including an Orthodox priest.The attacks in Moscow and Dagestan led to heavy criticism of the authorities and special services for failing to prevent them.ISIS, which claimed responsibility for the Crocus City Hall attack, praised the attacks in Dagestan, but no one has officially claimed responsibility for the killings.ISIS has repeatedly pledged to target Russia over its support of Syrian leader Bashar al-Assad, who has waged a military campaign to quash the group in the Middle East.AFP contributed reporting.