A deliberately set fire at a Tallinn building used by Milrem Robotics did not disrupt its deliveries of military ground robots to Ukraine, CEO Kuldar Väärsi told Reuters on 19 August 2026. Estonian prosecutors said three suspects had been detained in Latvia.

The Milrem arson case fits in a broader pattern of suspected or confirmed sabotage against Ukraine’s military supply chain. Similar attacks throughout Europe have hit plants making drones, thermal optics, and other equipment for the front. Milrem supplies unmanned ground vehicles (UGVs) that help Ukrainian units move supplies and evacuate wounded without putting drawing upon valuable manpower.

The fire broke out overnight on 15 August in Tallinn’s Lasnamäe district after a resident reported suspicious activity. Nobody was injured, and Milrem has not disclosed what was damaged.

Milrem says it is one of only two foreign suppliers with unmanned ground vehicle (UGV) fleets in active Ukrainian service and expects more than 200 of its systems to be operating there by year-end.

The Netherlands is funding more than 150 additional Milrem vehicles for Ukraine. In June, Milrem and VDL Defentec opened a Dutch production line to support the delivery of more than 100 THeMIS UGVs. Väärsi the fire had not affected production, supply chains, or delivery schedules for this year or next.

Unmanned ground vehicles (UGVs) are tracked or wheeled machines with no crew aboard. ArmyInform reported that Ukrainian troops use them to carry ammunition, fuel, and food along exposed routes. A Ukrainian commander identified only as Nazar told ArmyInform that frontline units still rely mainly on UGVs for logistics, although some robots carry explosives.

Three suspects detained as investigators examine possible Russian role

State Prosecutor Gardi Anderson said prosecutors suspect all three detainees of taking part in the arson. Latvian authorities are holding them while the two countries arrange their transfer to Estonia. An Estonian court approved prosecutors’ requests to place two in pretrial detention. A decision on the third remained pending.

Estonian Prime Minister Kristen Michal said investigators were examining whether the fire was the result of sabotage and whether Russia was involved. Authorities have not disclosed the suspects’ alleged motive, whether anyone directed them, or released evidence connecting the attack to Moscow.

Arson has hit other European suppliers to Ukraine

In March, a fire destroyed nearly all of the production capacity at a Czech plant that makes drones and thermal optics for Ukraine. Authorities detained four suspects while investigating possible terrorism and Russian involvement.

Lithuania also charged six people over an attempt to burn a factory supplying radio-wave scanners to Ukraine. Investigators said Russia-based organizers with GRU links coordinated the operation and connected the network to attempted attacks elsewhere in Europe.

Russia has denied Western accusations that it conducts sabotage in Europe.

Estonia is investigating whether Russia was behind a suspected arson attack at a Tallinn building used by Milrem Robotics, Prime Minister Kristen Michal said on 18 August.

Officials have not released evidence yet connecting Moscow to the fire.

The fire hit a site used by a defense contractor that makes unmanned ground vehicles, including THeMIS vehicles used in Ukraine. The Estonian investigation into the Milrem fire comes amid suspected or confirmed arson plots against other European factories supplying Ukraine.

Estonian prosecutors said the fire, which began overnight into 15 August, may have been deliberately set. A resident reported suspicious activity nearby. Investigators identified suspects and asked a court to detain them. No one was injured, and Milrem CEO Kuldar Väärsi told the Estonian outlet Postimees that it was too early to assess the damage.

The company executive said the site was not an office building but declined to identify its contents or what was damaged, including whether unmanned ground vehicles were inside. The company has not said whether production or deliveries were affected.

Milrem’s THeMIS vehicles have operated in Ukraine since 2022. By 2023, the company had delivered 15 of the vehicles to Ukrainian forces and border guards. A Dutch-funded order for more than 150 additional vehicles followed in 2025. A new Dutch production line began making them in June 2026 and handed over its first vehicles for Ukraine.

Other factories supplying Ukraine have faced arson

In March, a fire damaged a Czech facility belonging to LPP Holding, which had supplied hundreds of AI-guided drones to Ukraine. Czech authorities investigated possible terrorism and later detained a fourth suspect.

In January, Lithuania charged six people over an attempt to burn a factory supplying radio-wave scanners to Ukraine. Investigators said Russia-based organizers with GRU links coordinated the operation and connected the network to attempted attacks elsewhere in Europe.

Estonia has traced earlier attacks to Russian intelligence

Estonia has also uncovered Russian-directed attacks on its own territory. In 2024, Estonia’s security service detained 10 people over a Russian-coordinated operation that included damaging cars belonging to then-Interior Minister Lauri Läänemets and a journalist and defacing monuments. Officials said the operation sought to spread fear and tension. Journalists from The Insider, Re:Baltica, and Delfi reported how the GRU recruited Baltic residents for vandalism and arson.

In 2025, an Estonian court found that a Moldovan national working for the GRU burned a supermarket as a trial run before firebombing a Ukrainian restaurant in Tallinn. His cousin filmed the second attack.

Those cases explain why investigators are examining a possible Russian role in the Milrem fire, but they do not establish who caused it.

Russia may expand hybrid attacks against Poland and the Baltic states, including infrastructure sabotage or false-flag attacks, Bloomberg reported on 12 August, citing an unnamed European intelligence official. 

The warnings come amid concern that Moscow wants to intimidate Ukraine’s supporters. The CIA warning follows Russian threats, incursions, alleged sabotage plots, and disinformation against Poland and the Baltic states. Most Western military aid reaches Ukraine through Poland, while the Baltic states rank among Kyiv’s strongest supporters. Sabotage of transport, energy, or communications can slow aid delivery and test NATO while hiding Russia’s role.

Separately, a European government official told Bloomberg that the CIA had warned countries in the region of a possible future Russian attack. The CIA declined to comment.

The same official said Russia might instead be creating the impression of an impending attack to sow fear as part of an information operation. The official saw no signs that Moscow was preparing a conventional attack or invasion.

Moscow tests NATO’s eastern flank

Poland and Lithuania had already raised similar concerns. In July, Poland said it had credible intelligence that Russia was planning new provocations. Lithuania later warned that Moscow might rebuild captured Ukrainian drones for false-flag strikes on critical infrastructure.

In September 2025, between 19 and 23 Russian drones entered Polish airspace, shutting down airports and damaging buildings. Poland closed four airports as NATO aircraft responded.

Meanwhile, five people are on trial in Lithuania over attacks allegedly organized for Russian military intelligence in 2024, Bloomberg reported. Lithuania has reinforced infrastructure sites and deployed troops since June.

These warnings and incidents place the CIA alert within a wider pattern of pressure on NATO’s eastern flank and Ukraine’s supporters. 

How Russia strikes without starting a war

Bloomberg cited several recent unexplained drone incidents in Germany alongside the CIA warning. Citing Die Zeit, Euromaidan Press reported that an explosive-laden drone struck the wing of a parked Ukrainian An-124 at Leipzig-Halle airport and failed to detonate. A US Defense Department official in Europe told CNN that Washington assessed the drone belonged to Russian intelligence. 

Bloomberg also reported that a cargo plane hit an unidentified object and that drones appeared over a military base the following day. It did not connect either incident to Russia.

More broadly, Russian hybrid operations have grown sharply since the full-scale invasion. CSIS found that attacks in Europe tripled from 2023 to 2024, after quadrupling the previous year. Separately, the US Helsinki Commission mapped nearly 150 operations in NATO territory attributed to or suspected of Russia between February 2022 and November 2024.

Retired Lt. Gen. Ben Hodges told Euromaidan Press in February that attacks on ports, railways, and cables can probe routes needed for NATO reinforcements. Their deniability raises the political cost of responding.

By hiding its role, Moscow can disrupt support for Ukraine and test NATO without openly starting a war.