Ambulances and vehicles of Russian emergency services are parked at site of a shooting outside Moscow. Reuters

In a statement, the Ministry of Foreign Affairs (MoFA) affirmed that the UAE expresses its strong condemnation of these criminal acts and its permanent rejection of all forms of violence and terrorism aimed at undermining security and stability in contravention of international law.

The Ministry expressed its sincere condolences and sympathy to the government and people of Russia, and to the families of the victims of this heinous crime, as well as its wishes for a speedy recovery for all the injured.

At least 40 people were killed and more than 100 injured the attack on a concert hall outside Moscow, Russia's Federal Security Service said.

"According to preliminary information, 40 people were killed and more than 100 were injured as a result of a terrorist attack in the Crocus City Hall," the Interfax news agency reported, citing the FSB.