At least 133 people are dead and more are injured after gunmen wearing camouflage attacked a concert venue on the outskirts of Moscow on Friday.
Russia’s Investigative Committee, which released the number of casualties, said in a statement that “unfortunately, the number of victims could increase.”
The flame and smoke from the concert could be seen from miles away.
Eleven people were detained, including four who were directly involved in the attack, according to a statement from the Russian Federal Security Service, or FSB.
The U.S. warned Russia earlier this month that it had information about a planned terror attack in Moscow, potentially targeting concerts, said National Security Council spokeswoman Adrienne Watson in a statement.
Witness videos on social media show at least three attackers firing at bystanders as they attempted to hide. Other images show people lying on the ground in the main concert hall before a fire breaks out and spreads, trapping some inside.
Several people were earlier spotted on the venue’s roof, which later appeared to collapse from the fire.
Moscow Mayor Sergey Sobyanin said “A huge tragedy has occurred” as the number of dead is expected to rise, and expressed his condolences.
Russian President Vladimir Putin has yet to comment directly on events, instead wishing a speedy recovery to the injured and expressing thanks to doctors through a senior administration official.
Russian Foreign Ministry spokesperson Maria Zakharova called on the international community to condemn the incident, calling it “a monstrous crime.”
Meanwhile, in Moscow and Saint Petersburg, people lined up to donate blood for victims.
