Dozens of people have reportedly been killed and more than 140 wounded in an attack at a concert venue near Moscow. Here is what we know about the shooting so far: Unidentified gunmen opened fire at the Crocus City Hall in Krasnogorsk near Moscow on Friday evening during a sold-out concert by the Russian rock group Piknik. Crocus City Hall is one of the largest and most popular music venues in the Moscow oblast. Forty people are reported dead and more than 140 wounded after the shooting as of 19.15 GMT, Russian state news agencies said, citing Russia’s Federal Security Service (FSB). The victims reportedly included children. Up to five gunmen were believed to be involved in the attack, which was later claimed by Islamic State in a post on Telegram which suggested that the attackers had managed to escape afterwards. The Russian national guard was searching for those who attacked the Crocus City Hall, Russian news agencies reported. A lawmaker said they had left the concert hall after searching the underground car park, ground and first floors. Videos emerged showing gunmen in tactical gear opening fire with automatic weapons as panicked Russians fled for their lives. The attackers also apparently detonated explosives, as the sounds of blasts could be heard in other videos from the attack. Tass, the state news agency, reported that people remained inside the building, which was almost completely engulfed in flames and that others were trapped on the roof. Spetsnaz units of Russia’s national guard as well as police and firefighters were at the scene. Earlier this month, western countries led by the United States had issued terror warnings and told their citizens not to join public gatherings in Russia. On 8 March, the US embassy wrote it was “monitoring reports that extremists have imminent plans to target large gatherings in Moscow, to include concerts, and US citizens should be advised to avoid large gatherings over the next 48 hours”.