Watch LIVE Russian response to mass shooting near Moscow

Law enforcement officers and emergency services have been deployed in response to an attack at Crocus City Hall

Police forces, ambulances, and fire brigades have been dispatched to Krasnogorsk, a city just outside of Moscow, where an attack on a large shopping center and concert venue happened on Friday evening.

A group of gunmen is reportedly responsible for the mass shooting and a big fire that has engulfed Crocus City Hall. RT is broadcasting live from the scene.

The Russian authorities consider the incident a terrorist attack.

At least 40 people were killed, according to a preliminary report by the FSB, Russia's domestic security service.