President of Russia, Vladimir Putin said Saturday that authorities have detained 11 suspects in the attack on a suburban Moscow concert hall that killed at least 115 people and left the sprawling venue a smoldering ruin.
The death toll in the attack has now risen to 133, according to latest reports.
In an address to the nation, Putin called it “a bloody, barbaric terrorist act” and said all four people who were directly involved had been taken into custody.
Putin claimed the suspects had tried to cross the border into Ukraine which, he said, tried to create a “window” to help them escape.
Ukraine has strongly denied any involvement in the attack.
Putin said Saturday that additional security measures have been imposed throughout the country and declared March 24 a day of national mourning.
The Islamic State group’s Afghanistan branch claimed responsibility for Friday’s attack in a statement.
The attack, which was the deadliest in Russia in years, came just days after Putin cemented his grip on power in a highly orchestrated electoral landslide and as the country’s war in Ukraine dragged into a third year.
Ukraine’s foreign ministry also denied that the country had any involvement and accused Moscow of using the attack to try to stoke fervor for its war efforts.
