Explained: Why Is Russia Refusing To Comment On ISIS Link To Moscow Attack

The Kremlin refused to comment Monday on the Islamic State group's claims that it was behind the deadliest attack in Russia in two decades, as rescuers searched for bodies amid the rubble of the burnt-out Moscow concert hall.

Eleven people have been detained in connection with the attack, which saw camouflaged gunmen storm into Crocus City Hall, open fire on concert-goers and set the building ablaze, killing at least 137 people.

Islamic State jihadists have said several times since Friday that they were responsible, and IS-affiliated media channels have published graphic videos of the gunmen inside the venue.

But in his only public remarks on the massacre, Russian President Vladimir Putin on Saturday pointed to a possible Ukraine connection, and no senior Russian official has commented on the IS claims.

"The investigation is still ongoing. No coherent version has yet been voiced," Kremlin spokesman Dmitry Peskov told reporters on Monday when asked why Russia had not addressed IS's claimed involvement.

"We are talking only about preliminary data. No version has been put forward yet," he added.

Officials expect the death count to rise further, as rescuers were searching the site for remains on Monday and 97 are still in hospital.

'Dealing with threats'

Putin has no plans to visit the site of the attack, on the northwestern edge of Moscow, Peskov said.

He will hold a meeting with Russia's security chiefs, government officials and the heads of Moscow and the Moscow region later Monday.

The Kremlin also expressed confidence in the country's powerful security agencies, as questions swirl over how they failed to thwart the massacre despite public and private warnings by the United States' intelligence apparatus.

In a series of late-night court hearings in Moscow that ran into the early hours of Monday, four of the suspects -- with bruises and cuts on their swollen faces -- were dragged in amid dozens of reporters who had assembled at the capital's Basmanny district court.

FSB officers wheeled one into the hearing on a gurney, his eyes barely open.

Peskov refused to comment on reports and videos on social media that showed bloody interrogations of the suspects after they were arrested on Saturday.

The court identified them as Muhammadsobir Fayzov, Shamsidin Fariduni, Rachabalizoda Saidakrami and Dalerjon Mirzoyev.

Russian state media said they were all citizens of Tajikistan.

Two of them pled guilty, the court said.

Three other suspects, whom Russian media identified as family members Aminchon Islomov, Dilovar Islomov and Isroil Islomov, were remanded in pre-trial detention on Monday.

One of those detained has Russian citizenship, the Interfax news agency reported.

All of those held in custody have been charged with terrorism and face up to life in prison. The Kremlin has pushed back at suggestions the death penalty will be re-introduced.

Removing rubble

At least 137 people, including three children, were killed, according to the latest toll by Russian investigators.

After walking through the theatre shooting spectators, the gunmen set fire to the building, trapping many inside.

Victims died both of gunshot wounds and smoke inhalation, according to Russia's Investigative Committee.

More than 5,000 people were in the concert hall when the gunmen stormed in ahead of a sold-out rock concert, Russian state media cited a spokesperson from the venue owner as saying Monday.

Rescuers will continue sifting through the rubble and clearing debris at the site until Tuesday evening, said Andrey Vorobyov, governor of the Moscow region.

"The task is to remove the rubble to make sure there are no bodies underneath," Vorobyov said in a Telegram post.

Putin on Saturday vowed "retribution and oblivion" to the "terrorists, murderers and non-humans" who carried out the "barbaric terrorist act".

He said the four assailants had been arrested while trying to flee to Ukraine, where they had secured a "window" to cross the border.

Mourning

The FSB has said the gunmen had "contacts" in Ukraine, without providing more details.

Ukrainian President Volodymyr Zelensky has denied any Ukrainian involvement.

The United States, which on March 7 warned about an "imminent" attack in Moscow by "extremists", has said IS bears "sole responsibility".

On Monday, French President Emmanuel Macron warned Russia against "exploiting" the attack to blame Kyiv.

Russia observed a day of national mourning on Sunday, with dozens coming to lay flowers at a memorial to the victims, and tribute posters were erected on the sides of buildings and at transport stops across the country.

Russian schools were holding special lessons on "terrorism," on Monday, with children wearing white ribbons in honour of the victims, state TV presenters said in a news bulletin.

Tajikistan's President Emomali Rahmon condemned the attack again on Monday, after Russian media reported the gunmen were Tajik citizens.

The attack "calls on all of us, especially parents, to once again pay even more serious attention to the education of children," he was quoted by Russian news agencies as saying.

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