On Saturday, Russia announced that it had arrested 11 individuals, four of whom were gunmen, in connection with the attack on a Moscow concert hall claimed by the Islamic State. The death toll from the attack has now risen to 115.

Russian President Vladimir Putin has not yet made a public statement regarding the attack, and the Russian government has not addressed the Islamic State's claim of responsibility. Some lawmakers have suggested a possible connection to Ukraine.

Gunmen wearing camouflage opened fire at the Crocus City Hall in Moscow's Krasnogorsk suburb on Friday during a concert by the band Piknik, marking the deadliest attack in Russia in at least ten years.

The Russian security service FSB reported that some of the attackers had fled towards the Russia-Ukraine border and that they had contacts in Ukraine but did not provide specifics. Some Russian lawmakers have insinuated Ukrainian involvement, although Ukraine has denied any connection to the attack.

The Kremlin confirmed that the head of the FSB had informed President Putin of the arrests, and the government warned that the death toll could continue to rise. Meanwhile, the search for victims at the concert hall is ongoing, with over 100 people still hospitalized.

The Islamic State claimed responsibility for the attack, saying its fighters targeted a large gathering in Moscow before retreating safely. The Russian authorities have labeled the incident as a terrorist attack but have not commented on the Islamic State's claim.

As of Saturday morning, 107 people remained hospitalized. Some of the suspects reportedly hail from Tajikistan, although Tajikistan's foreign ministry stated that they had not received any information regarding their citizens' involvement.

In response to the tragedy, Muscovites lined up in the rain to donate blood, and memorial posters with a single candle adorned some bus stops in Moscow.