Europe targeted by spiralling campaign of sabotage and Russia is the chief suspect
Germany has blamed Russia for an attack on Leipzig airport but there has been a series of suspicious incidents elsewhere.
As summer temperatures in Europe smashed records and many politicians shifted to holiday mode, Russia remained focused on its war.
Not only did its military attacks across Ukraine intensify last month, becoming ever more deadly for civilians, Russia also appears to have escalated its sabotage campaign across Europe.
This time, military and defence sector sites were the prime target.
A full month after drones packed with explosives were found at Leipzig's airport, used by Ukraine to transport military goods, Germany's interior minister has declared that "Russia is responsible".
Russia's President Vladimir Putin is demanding proof, as always, and his officials call the accusation "absurd".
But the drones were just a dramatic start. August then brought a series of suspicious fires at defence facilities from Italy to Estonia.
Some of the affected countries have already blamed Russia; others are still investigating and some fires may eventually be ruled accidental, exactly as such attacks are designed to seem.
Poland's interior minister is clear.
"There are many, many signals that Russia is changing its strategy and intensifying its activities, including terrorist and sabotage activities," Marcin Kierwiński said, warning people to be on their guard.
Germany says Russia behind Leipzig airport drone attack
EU and Nato vow to step up pressure on Russia after 'new escalation' in Germany
August campaign across Europe
4 August Germany: The first drone at Leipzig airport is discovered.
10 August Bulgaria: A major fire breaks out at a factory of the defence firm EMCO, with initial reports that a truck ignited during a fuel delivery.
13 August Italy: A fire at KNDS Ammo Italy outside Rome triggers a large explosion.
The local prosecutor is looking into possible outside interference, La Repubblica newspaper reports. Publicly, his office will only confirm that a case has been opened for negligent disaster against "unknown persons".
15 August Estonia: The Milrem Robotics factory in Tallinn, which the Kyiv Post says supplies drones to Ukraine, goes up in flames. Two suspects are arrested.
Estonian Prime Minister Kristen Michal says the possibility of Russian sabotage is being "taking seriously" by investigators.
25 August Slovakia: Police announce they have averted an arson attack on a Ukrainian-owned drone manufacturer and seized a "large amount of incendiary mixture". The firm itself blames Russia and police arrest three suspects who they say were "following orders". Slovakia is Russia's close ally in Europe.
30 August Poland: A country which is heavily targeted for sabotage reports two more fires.
One is in Lublin at a company which produces helicopter components. Prime Minister Donald Tusk said arson "cannot be ruled out".
An attack on the drone producer, WB Group, is clearer cut. A masked man is caught on CCTV throwing incendiary devices. Tusk calls it a "continuation of Russia's escalatory activities".
The pattern has continued into September with two Bulgarians arrested in Munich, Germany, for suspected arson after throwing incendiary devices from a car at defence firm Rhode & Schwartz.
Why is this happening now?
Attacks on military and defence targets are not new, although previous acts of sabotage linked to Russia include more puzzling targets - such as an Ikea store and a Polish paint store.
The novelty now is the concentration of cases.
"The intensity of military sites being attacked we've seen over the past couple of weeks is unusual," Daniela Richterova of the Department of War Studies at King's College says.
She links the spike to developments in Russia's invasion of Ukraine.
"We've basically seen Ukraine take the war to Russia and strike deep inside Russian territory…They [Moscow] are under pressure, they have to do something."
Whilst some sabotage is staged to sow chaos or fear, Richterova believes the Kremlin's aim right now is "coercive signalling": pressuring countries to stop supporting Kyiv by raising the stakes.
After a slow start, Germany is Ukraine's biggest supplier of military aid.
There are other theories.
To some, Russia is less concerned about "turning off the taps" of supplies to Ukraine and more about testing Nato for weaknesses.
"Russia is probing the boundaries of what's acceptable and collecting information on the results. They find out what works, and what's vulnerable," argues Keir Giles from the Chatham House think tank.
He sees the sabotage campaign as preparation for the "next phase", as he puts it, of Russia's aggression in Europe.
