Russian President Vladimir Putin has vowed to track down and punish those responsible for the attack on the Crocus City Hall near the capital, Moscow.
Gunmen burst through the doors of the building on Friday night, opening fire on those who had gathered in the foyer and main auditorium.
As of Saturday evening, the official death toll had been set at 133 with more than 120 wounded.
Four gunmen have been captured – with one apparently telling the authorities that he had been approached on messaging service Telegram.
A video on social media shows him admitting that he was offered a large sum of money to carry out the attack.
Reuters reports that militant group the Islamic State has claimed responsibility for the rampage, but there are indications that Russia is pursuing a Ukrainian link.
However, Kyiv has denied any role in the attack and the United States has cautioned Russia to establish the truth.
However, President Putin has addressed the nation saying that a total of 11 people were arrested after they had tried to hide and move towards the Ukrainian border.
Putin has labelled the incident as “international terrorism” and says he is ready to work with any nation that wants to defeat it.
Footage from the attack shows camouflage-clad gunmen opening fire with automatic weapons at concert-goers.
People rushed to the doors as gunfire rang out.
A huge fire then engulfed the roof of the building – believed to be lit using petrol from containers.
Police chased a Renault vehicle that was spotted in the Bryansk region, about 340 km south-west of Moscow.
A car chase ensued after the occupants disobeyed orders to stop, and the vehicle overturned.
A pistol, a magazine for an assault rifle, and passports from Tajikistan were found in the car.
There has been a swift response from countries around the world with the United Nations Security Council condemning what it calls a “heinous and cowardly terrorist attack”.
