At least five heavily armed, masked men dressed in military fatigues barged into a concert hall in the Russian capital, Moscow, on Friday evening and opened fire, killing at least 60 people and injuring 145 others. Their use of gunfire and grenades set the concert hall ablaze.
The attack took place at the Crocus City Concert Hall in Moscow's Krasnogorsk suburb just as members of the audience were taking their seats ahead of a planned concert.
Russian security services said that between two and five people "wearing tactical uniforms and carrying automatic weapons" had opened fire on guards at the entrance and then started shooting at the audience.
Videos posted on social media showed armed men mowing down people gathered at the entrance to the concert hall, while other videos from inside the hall showed the audience and staff taking cover behind seats and the stage as they tried to head towards the exit. At least 100 people escaped through the theatre's basement, while others found shelter on the roof of the building, Russia's emergency services ministry said.
Russian Health Minister Mikhail Murashko said at least 115 people were brought to hospitals in the city, including five children. He described the condition of one victim to be grave. Of the 110 adult patients, 60 were described to be in serious condition.
As security officials worked to trace the attackers, fire services worked to put out the blaze. At least three helicopters were used to help contain the fire, and it took them several hours to finally contain and put it out.
The attack comes weeks after elections in Russia re-elected Putin. Officials said that Putin was informed about the attack minutes after it began and received continuous updates on the situation but did not issue a public statement. However, the Russian Foreign Ministry described it as a terrorist attack and called on the international community to condemn the "odious crime".
The US condemned the crime but said thus far, it does not appear to be linked to the conflict in Ukraine as pro-Ukraine militant groups also denied responsibility. The European Union, France, Spain, Italy and the UN, among several other countries, condemned the attack.
While Russia has been the target of terrorist attacks, including by Islamic militant groups, the Islamic State has not claimed an attack of this scale in Russian territory before. The Islamic State was the target of Russian aggression in Syria and northern Iraq.