A fire at a Polish plant that makes drone parts for Ukraine's and Poland's militaries is being investigated as possible sabotage by a foreign intelligence service, Militarnyi reported. Poland's National Prosecutor's Office opened the case on two counts: foreign-intelligence activity against the country and a terrorist offense.

Fires and break-ins like this fit a widening pattern — the factories and supply lines that keep Ukraine armed are increasingly targets far from the front line. Across the continent, prosecutors keep opening the same kind of arson case against plants tied to Ukraine's defense.

A masked intruder and a two-hour fire

The fire started shortly after midnight on 31 August in the assembly hall of the WB Electronics plant in Skarżysko-Kamienna and spread to the storage rooms. Five crews put it out in under two hours. No one was hurt, but the storage rooms were destroyed, leaving at least 15 million zloty ($4 million) in damage. The plant had no permanent guards on site; a security company monitoring it remotely reported the fire.

Prosecutors say the blaze was set deliberately with a planted charge of flammable material, and no one has been charged. Security cameras recorded a masked person who climbed a fence and got onto the site.

Why Poland is looking at Moscow

Czesław Mroczek, deputy head of Poland's Interior Ministry, told RMF FM radio that many signs point to arson, and that a Russian trail is the obvious inference. An attack on the defense industry can suggest Russian involvement, he said, since European states have faced sabotage for years while backing Ukraine. Mroczek said protection plans for key defense plants must be richer than what this site had. No one has been detained, and investigators are still tracing how the intruder got in and who may have ordered it.

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What the plant actually makes

WB Electronics is the core of WB Group, Poland's biggest private arms holding, whose firms build reconnaissance and strike drones such as the FlyEye and the Warmate. The Skarżysko-Kamienna site itself makes drone components for unmanned systems, used by both Polish and Ukrainian forces. Ukraine received FlyEye drones back in 2022 under its Army of Drones program, and in 2025 WB Group launched drone production inside Ukraine.

Slovak police foiled a planned arson attack on a drone factory in the country's east, the force said on 25 August. Investigators charged three foreigners with preparing the attack on commission and seized incendiary material and equipment at the scene. The plant belongs to the Ukrainian drone maker Skyeton, Militarnyi reported.

Had the attack in Slovakia gone ahead, it risked a large fire, danger to life and health, and damage on a large scale, police stated. About 70 employees could have been in the building at the time, by preliminary estimates. Property inside the production hall is worth tens of millions of euros, according to the findings so far.

Officers seized a larger quantity of incendiary mixture, along with tools, mobile phones, an action camera, and a hand-made plan. The police Criminalistics and Expertise Institute gave a preliminary finding that the substance was a mixture of gasoline and polystyrene, commonly called napalm. Slovakia's anti-crime unit ÚBOK, part of the Police Presidium, identified the people preparing the attack and stopped it. Nobody was hurt and no property was damaged, police said.

The charges, and where the three were detained

An ÚBOK investigator charged the three foreigners with preparing a particularly serious crime of general endangerment, committed as co-perpetrators on order. Officers detained two of them in Slovakia, and the investigator moved to have both taken into custody. German authorities detained the third on a European arrest warrant. The investigation continues, and the legal classification of the men's actions may still change.

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The plant, and a company Russia has already hit

Slovakia, a NATO and EU member, borders Ukraine on its eastern edge. Skyeton builds the Raybird, a fixed-wing reconnaissance drone that has served with Ukraine's Armed Forces since 2018 and stays airborne for up to 28 hours. The company began production in Slovakia in 2024, and more than €10 million in foreign investment went into the plant, one of several sites Ukrainian firms opened abroad to cut the risk of Russian attacks.

That risk is not theoretical. Russia destroyed Skyeton's Kyiv office in May, and the company said it had already spread production capacity across Ukraine and abroad in anticipation.

A Skyeton representative told Militarnyi:

"The recent attempt on our production in Slovakia is another sign that Ukrainian arms makers are already a bone in their throat, which means we are on the right path." 

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Arson against Ukraine's defense partners in Europe

Companies working for Ukraine have been hit across several countries this year and earlier. 

In March, suspects who claimed a pro-Palestinian motive set fire to the Pardubice production of Archer, a Ukrainian maker of thermal imaging sights, destroying nearly all of the company's capacity in Czechia.

Estonia opened a Russian-link investigation this month into a suspected arson at a military robot maker supplying Ukraine, and Lithuania charged six people in January over an attempt to burn a factory that supplied radio-wave scanners. 

A powerful explosion of undetermined cause hit EMCO, one of Bulgaria's largest private arms makers, which produces artillery ammunition for Ukraine, on 10 August.