Russia has been suspected of launching several attacks on weapons and defence factories across Europe as part of a ‘destabilisation campaign’.

The alleged operations are thought to be designed to test NATO’s resolve while stopping short of triggering Article 5, which is the alliance’s mutual defence clause.

Last week,Latvia detained three of its own nationals over a suspected arson attack on a drone manufacturer in neighbouring Estonia.

A building belonging to Milrem Robotics, a Tallinn-based company supplying weapons to Ukraine, was set alight on August 15.

Estonian Prime Minister Kristen Michal has said the country is investigating whether the fire was an act of sabotage and whether Russia was involved.

It comes after a series of suspected attacks involving companies that are supplying Ukraine’s military have also been attacked.

A Nato official said Russia had ‘accelerated its destabilisation campaigns’ against member states in recent years, through the likes of cyber attacks, assassination attempts and sabotage.

Western intelligence sources have even claimed that the Kremlin is using local criminal gangs to carry out the attacks.

The campaign has been described as the Kremlin’s ‘hybrid war’ against the the West to increase tensions between Nato allies and deter support for Ukraine.

Since Russia’s full-scale invasion of Ukraine in February 2022, there have been a number of unexplained fires and explosions at sites across Europe.

This month, explosions were reported at major arms manufacturers in Bulgaria and Italy.

On August 10, a major blast hit a plant belonging to EMCO, one of Bulgaria’s largest private arms manufacturers, which produces 155mm artillery ammunition for Ukraine.

The initial fire was reportedly started by a blaze in a lorry parked near a storage warehouse.

Three days later, another explosion hit a munitions factory operated by KNDS Ammo Italy in Colleferro, near Rome.

The cause was reportedly an unexplained fire in a gunpowder processing unit.

Officials in both Italy and Bulgaria, however, have played down any links with Russia.

Nato Secretary General Mark Rutte has described suspected Russian sabotage as ‘reckless and dangerous’, calling for the alliance’s response to be ‘clear, swift and decisive’.

A Nato official said the alliance was strengthening its ability to counter such operations and monitoring hostile activity carried out through proxies.

The official said Nato would remain prepared to ‘deter and defend against any threat’ to its members.

Earlier today, it was revealed that Ukraine marked its Independence Day by targeting Vladimir Putin’s online shopping hubs.

Three Ozon marketplace logistics centres were engulfed by flames following the overnight strikes.

The attacks unfolded on the day UK prime minister Andy Burnham was making his first trip as leader to Kyiv.

Ozon is often referred to as the ‘Amazon of Russia’ and supports Moscow’s military, Ukraine says.

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