On Friday night, the extremist Islamist militant group Islamic State claimed responsibility for the mass shooting that left at least 60 people dead and dozens more wounded in a Moscow suburb.

But the Kremlin has yet formally to accuse any organisation, nation or individual. IS has on occasion in the past falsely claimed credit for attacks, though the brutality unleashed at the concert hall matched Islamic State tactics.

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In the swirl of confusion and terror, speculation also grew that the gunmen who carried out the mass shooting may have been linked to the Ukraine war, such as a so-called "false flag" operation by Russia that it could pin on Kyiv to garner more domestic support.

The Ukrainian foreign ministry strongly rejected what it said were claims by Russian officials that Ukraine was involved.

It said it viewed any such allegation "to be a planned provocation by the Kremlin to further fuel anti-Ukrainian hysteria in Russian society, create conditions for increased mobilisation of Russian citizens to participate in the criminal aggression against our country and discredit Ukraine in the eyes of the international community".

The ministry noted the Russian regime has a "long history of bloody provocations by its special services", adding: "There are no red lines for Putin's dictatorship. It is ready to kill its own citizens for political purposes, just as it has killed thousands of Ukrainian civilians during the war against Ukraine as a result of missile attacks, artillery shelling and torture."

As well as waging a war against Ukraine, Russia also has problems with Islamist extremism - an issue which it had in the past cooperated with the UK and the US on, though that has long since stopped as relations froze.

US embassy issued warning of extremist attacks

On 7 March, the US embassy in Moscow issued a warning to US citizens in the Russian capital to avoid large crowds for the next 48 hours because of reports "that extremists have imminent plans to target large gatherings".

It did not give any further details about what kind of extremists had triggered the alert.

Kremlin weaponises information to influence public

In the aftermath of any terrorist attack anywhere in the world, accurate information is difficult to find. It typically takes time to understand what has happened and who was involved.

However, the atrocity on Friday evening has struck in a country where the truth is often buried or distorted as the Kremlin weaponises information and disinformation to influence its people and the world - especially at a time when it is locked in a war against Ukraine.

Sam Greene, a director at the Centre of European Policy Analysis, said in a post on the social media site X, that the attack was "an act of terrorism, full stop".

"Having failed to prevent it, the Kremlin will likely look for a way to use it, which may well mean blaming Ukraine," he wrote, while cautioning: "The fact that the Kremlin will use the attack for political purposes does not mean it was a false flag."