Just after midnight local time on 31 August 2026 (22:15 UTC on 30 August), an unidentified man broke into a WB Electronics plant on Obuwnicza Street in Skarżysko-Kamienna, about 150 km south of Warsaw, smashed a window into one of its production halls, and threw in a backpack carrying an incendiary device, according to TV Republika. The plant manufactures drone and loitering-munition components for the Polish and Ukrainian militaries. The resulting fire was extinguished; the man tried to plant a second device but was stopped by security, then fled while wearing a GoPro camera that appeared to be recording the break-in, per the same report. No one was injured. Police, prosecutors and Poland's domestic intelligence agency, the Internal Security Agency (ABW), are investigating, and a manhunt for the suspect was underway as of this writing.
Firefighters found no hazardous material once the blaze was out
Five fire brigade units, 25 firefighters in total, responded to the alarm and had the fire extinguished within roughly two hours, according to Interia's report of the fire department spokesman's account. Crews cut the building's power, then checked it with a thermal camera and hazardous-substance detectors; neither found any remaining risk. WB Group spokesman Remigiusz Wilk told TV Republika the blaze was confined to one room of about 60 square meters. In a separate interview carried by Interia, he said an employee spotted the fire on the site's monitoring system and began extinguishing it before firefighters arrived. Wilk said the company expects to resume production at the affected hall quickly.
WB Electronics is Poland's largest private defence manufacturer
WB Electronics, part of the WB Group, is Poland's largest private defence company and a supplier to the Polish army, building digital command systems, automated fire-control systems, communications equipment, and unmanned and strike systems, including the Warmate loitering munition and the FlyEye reconnaissance drone. The Skarżysko-Kamienna site produces composite and control structures for unmanned aerial systems. Some of what the plant produces goes to Ukraine's armed forces, which has made WB Group a named target of Russian and Belarusian sabotage warnings from Polish officials this year.
An anti-intrusion sensor triggered before the break-in
Corroborating outlets place the same intruder at the site's perimeter before the break-in: an anti-intrusion sensor triggered shortly before the fire was reported, and surveillance footage showed a masked figure attempting to enter through the perimeter fence, with a backpack and a sweater found abandoned nearby, according to UNN.ua. Jacek Dobrzyński, spokesman for Poland's special-services coordinator, said ABW officers were already on site and the matter was being taken seriously, but cautioned it was "too early to speak with certainty of an act of sabotage," per dpa. Wilk told TV Republika he could not comment on the plant's specific security measures, saying protection looks different "in peacetime, during a crisis, and during a war."
The fifth site tied to Ukraine's supply chain to catch fire in August
Skarżysko-Kamienna is the fifth site tied to Ukraine's military supply chain that AirVeto has recorded catching fire, exploding, or coming under sabotage suspicion in August 2026, after an explosive-laden drone found at Leipzig/Halle Airport on 4 August, a fire at the EMCO ammunition plant near Belitsa, Bulgaria on 10 August, an explosion at the KNDS Ammo Italy plant at Colleferro on 13 August, and a deliberate arson fire at a Milrem Robotics building in Tallinn on 15 August. AirVeto's own reconstruction of that pattern, and what investigators have and haven't established about it, is at Four hits on Ukraine's defence supply chain in eleven days. Skarżysko-Kamienna is the most directly witnessed of the five: unlike the other four, this one has a specific, reported account of the intrusion and ignition method, not just a fire under investigation.
Wind conditions over Skarżysko-Kamienna
At 22:00 UTC on 30 August, close to when the fire was reported, the 80 m surface layer over Skarżysko-Kamienna showed SSW wind at 21 km/h. At 2,000 m the flow shifted to WSW at 31 km/h; at 3,000 m it shifted further, to W at 38.5 km/h, a markedly stronger flow aloft than at the surface. At surface level, that flow would have carried smoke from the Obuwnicza Street building north-northeast, roughly toward the town centre - consistent with firefighters finding no hazardous readings once the blaze was out. This reconstruction is based on reporting by TVP World, dpa (via Yahoo News), Interia, UNN.ua and TV Republika (via niezalezna.pl), and on AirVeto's wind-model data for the event window. How AirVeto builds this field, and where it is reliable, is described on the methodology page.