Four men accused of gunning down scores of people at a concert outside the Russian capital, Moscow, have been charged with terrorism after appearing in a courtroom showing signs of severe beating.

The charges late on Sunday came as Russia lowered flags to half-mast for a day of mourning over the deadliest attack inside the country for two decades.

At least 137 people, including three children, were killed in the ISIL (ISIS) claimed attack. Another 182 people were wounded and health officials say some 40 of them were in “critical” or “extremely critical” condition.

Moscow’s Basmanny District Court identified the four suspects behind the attack as Dalerdzhon Mirzoyev, 32; Saidakrami Rachabalizoda, 30; Shamsidin Fariduni, 25; and Mukhammadsobir Faizov, 19.

The men – all of whom are citizens of Tajikistan – were charged with committing a group terrorist attack resulting in the death of others. The offence carries a maximum sentence of life imprisonment.

They were all ordered held in pre-trial custody until May 22.

The Associated Press news agency, citing court officials, said Mirzoyev and Rachabalizoda admitted guilt for the attack after being charged.

Russian media had reported that the men were tortured during interrogation by the security services and unverified and brutal videos of the suspects’ interrogations have been circulating on social media.

At court, Mirzoyev, Rachabalizoda and Fariduni showed signs of heavy bruising, including swollen faces, while Faizov was brought to court from a hospital in a wheelchair and sat with his eyes closed throughout the proceedings. He was attended by medics while in court, where he wore a hospital gown and trousers and was seen with multiple cuts.

Rachabalizoda also had a heavily bandaged ear.

Russian media said on Saturday that one of the suspects had his ear cut off during interrogation.

President Vladimir Putin, who has pledged to punish those behind the “barbaric terrorist attack”, said the four men had been arrested while trying to flee to Ukraine. Kyiv has strongly denied any connection to the attack.

Putin has made no public reference to ISIL’s claims of responsibility.

He said seven others have also been taken into custody.

Dmitry Medvedev, the deputy chairman of Russia’s Security Council, said Russia would target those behind the deadly shooting wherever they were from and whoever they were. He had previously spoken of the need to meet “death with death” and some legislators have begun to discuss whether the death penalty should be re-introduced.

In video footage published by Russian media and Telegram channels with close ties to the Kremlin, one of the suspects said he was offered money to carry out the attack at the Crocus City Hall.

“I shot people,” the suspect, his hands tied and his hair held by an interrogator, a black boot beneath his chin, said in poor and heavily accented Russian.

When asked why, he said: “For money.”

The man said he had been promised half a million roubles (a little more than $5,000). One was shown answering questions through a Tajik translator.

ISIL said on Telegram that the attack was carried out by four of its fighters “armed with machine guns, a pistol, knives and firebombs”.

A video lasting about a minute and a half, apparently filmed by the gunmen, has been posted on social media accounts typically used by ISIL, according to the SITE intelligence group.

The video – which appears to have been filmed from the lobby of the concert venue – shows several individuals with blurred faces and garbled voices firing assault rifles with inert bodies strewn on the floor and a fire starting in the background.

The White House said the United States government shared information with Russia early this month about a planned attack in Moscow, and issued a public advisory to Americans in Russia on March 7. It said ISIL bore sole responsibility for the attack.

Russian officials have bristled at the US public comments on the attack, the first of which were made shortly after news of the attack had broken, and say Russian investigators must be allowed to make their own findings. (Al Jazeera)

•PHOTO: A man suspected of taking part in the attack of a concert hall that killed 137 people in Moscow is brought into the Basmanny District Court in Moscow on March 24, 2024 [Tatyana Makeyeva/ AFP]

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