AT LEAST 14 suspects have been detained in a terror attack that killed scores of people at a Moscow concert hall.
Videos have been shared online of the men being brutally interrogated.
ISIS-K, a group associated with the Islamic State group, has claimed responsibility for the attack.
The Islamic State group-linked news agency Amaq released footage that it claimed was body camera video.
Here’s what we know about the suspects.
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Shamsuddin Fariddun
Four suspects have been charged so far with acts of terrorism.
Among them is 25-year-old Shamsuddin Fariddun, who is said to have been born in Tajikistan.
Fariduni's face appeared to be severely swollen when he was brought to Moscow's Basmanny district court.
According to Russian state media RBC, Fariddun was in Turkey a month before the incident.
The photos were allegedly taken on February 23 with some indicating the geolocation as Aksaray, Istanbul.
The court reported that the suspect said he was born in 1998 in Tajikistan and has an eight-month-old child.
Another state media organisation RIA stated that the accused said that he worked at a parquet factory in Podolsk and was registered in Krasnogorsk.
Dalerdzhon Mirzoyev
Dalerdzhon Mirzoyev pleaded guilty to all charges against him.
The 32-year-old was reportedly living in Novosibirsk with relatives, according to state media agency Lenta.ru.
The unnamed source claimed that Mirzoyev was residing there for three weeks as a taxi driver.
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The same person stated that the Tajik national has four children and a wife.
Like the other suspects, Mirzoyev appeared to be injured when he was seen in court.
Mukhammadsobir Faizov
Mukhammadsobir Faizov is said to have worked as a hairdresser in an Ivanovo barbershop and was born in 2004.
State-run TASS media noted that the 19-year-old does not have a wife or children.
The suspect appeared to be in a wheelchair and was missing an eye.
Saidakrami Murodali Rachabalizoda
Saidakrami Murodali Rachabalizoda also pleaded guilty to the charges.
The Tajik national was born in 1994, and was among the suspects to have been injured.
The suspect was seen covered in cuts and bruises, and his ear was reportedly severed.
According to Russian government-controlled news agency Kommersant, he is reportedly married with a child.
Three more suspects have been arrested in connection to Friday’s terrorist attack in Moscow that left 137 people dead.
Aminchon, Dilovar and Isroil Islomov
Brothers Aminchon and Dilovar Islomov, along with their father, Isroil Islomov, are accused of aiding and abetting terrorism.
After appearing in Basmanny Court they were sentenced to pre-trial detention at a maximum security facility until May 22, 2024.
The defendants, who all say they are innocent, are accused of being part of the ISIS Cell that conducted the attack.
They are also accused of assisting in planning the escape of the gunmen who opened fire at concert-goers at Crocus City Hall.
It's alleged that Dilovar Islomov is the previous owner of a white Renault car that authorities claim was the getaway vehicle for the Crocus City Hall shooters.
The trio are accused of conspiring with one of the other alleged attackers, Shamsidin Fariduni.
What happened in Moscow?
Scores of people at the Crocus City Hall were gunned down on Friday night in the deadliest attack inside Russia for two decades.
Located on the outskirts of Moscow, Crocus City Hall was preparing to host a concert by the rock music group Picnic.
However, the event took a tragic turn when, just after 20:00 (17:00 GMT) on Friday evening, gunmen stormed into the foyer.
Surveillance footage captured at least four assailants firing indiscriminately before they advanced into the main concert hall, where they continued their attack.
Flames later engulfed the façade, while glass on the top two floors of the seven-storey building blew out.
It took 10 hours for the fire to be contained.
Russian President Vladimir Putin tried to claim that the four gunmen were “headed for Ukraine” after they fled the scene, with no evidence.
Ukrainian President Volodymyr Zelenskyy rejected the claim that his country had been involved in the attack.
The White House reiterated that Ukraine had “no involvement whatsoever” in the massacre.
How many people died in the Moscow attacks?
The official number of those left injured rose to 154 and Russian authorities raised the death toll to 139 people, the Investigation Committee said.
It also said 62 bodies have been identified.
Russian investigators said at least three children were among the dead.