A fire at a Starlink satellite station in central Poland was a deliberate "act of sabotage", a government minister has said.

Polish Deputy Prime Minister Krzysztof Gawkowski said the fire in the Masovian Voivodeship province was "deliberately designed to disable the station... disrupting internet access for various institutions, including the Ukrainian army".

He told Polish public broadcaster TVP Info an investigation was ongoing but "many indications suggest" the attack fits into a "new Russian doctrine of attack". The Kremlin has not commented.

Meanwhile, Denmark's intelligence service issued a new threat assessment saying it expects Russia to escalate hybrid warfare in the coming months.

It said an attack remained "highly unlikely" but warned of "a low but growing risk" that Russia could launch a limited military attack against Nato countries.

In recent weeks a number of European Nato members have said Russia may be preparing attacks to test their commitment to supporting Ukraine, which Moscow denies.

Earlier this month, Germany blamed Russia for an attempted drone attack on Leipzig/Halle Airport, while France has ordered a plan to protect critical infrastructure and defence industry sites.

Hybrid warfare or hybrid attacks are loose terms which tend to describe non-military methods designed to exert pressure and destabilise an adversary - for example cyberattacks, sabotage or misinformation.

Proxies are often used to carry out the attacks and Russia always denies involvement, despite growing evidence to the contrary.

Europe targeted by spiralling campaign of sabotage - and Russia is the chief suspect

The fire at the state-owned Polish satellite station broke out on Wednesday night in Wola Krobowska. It remains operational.

The deputy prime minister said it transmits internet traffic through Poland to countries including Ukraine, and uses SpaceX systems that provide connectivity via Starlink terminals.

Asked about the incident at a news conference with Bulgaria's leader on Thursday, Polish Prime Minister Donald Tusk said he disliked "labelling something as sabotage versus an accident without 100% certainty, but it looks bad".

Also on Thursday, Moldova's president said four Russian drones crossed into its airspace, with at least one exploding, while Romania's defence ministry said one drone crashed in its territory.

On Wednesday Poland also said a Russian military helicopter briefly violated its airspace, forcing it to scramble fighter jets.

Russian President Vladimir Putin has repeatedly said Moscow does not plan to attack Nato states.

Earlier this month, Russian Foreign Minister Sergei Lavrov said it was Europe speaking about preparing for war, adding: "If Europe attacks Russia, it will be a completely different war [from that in Ukraine], and it will be very short."

Putin launched a full-scale invasion of Ukraine in 2022, and Moscow currently controls about 20% of Ukrainian territory, including the Crimea peninsula annexed in 2014.

Ukraine is now experiencing round-the-clock attacks and near constant alerts.

In Kharkiv, six people were killed and 12 others injured in a Russian strike on a farm in the village of Stara Hnylytsia, Ukraine's state emergency services said.

It said they were agricultural workers sorting vegetables, with the head of the Kharkiv region adding that four were women.

Onions covered the floor where the six farm workers were killed in Kharkiv

In Kyiv, there were multiple explosions on Wednesday night as drones, ballistic and cruise missiles landed or were intercepted over the city.

In the past 24 hours, a bakery, a pharmaceutical plant and a jewellery workshop were all hit. Strikes on several data centres also caused internet disruptions in areas of the city.

Two people were killed and eight others injured overnight, emergency services said. One was killed when fragments of a drone landed close to a maternity hospital.

The hospital's director said a woman gave birth to a baby boy in a shelter during that attack, adding: "Even on such a terrible night, life goes on."

Russia's defence ministry said it had hit Ukrainian defence facilities, logistics and telecom centres, as well as vessels used by the military.

Watch: Ukraine's race to counter a new type of Russian drone

Ukrainian President Volodymyr Zelensky, who is in New York for the UN General Assembly, accused Russia of deliberately targeting civilian infrastructure. But it is sometimes hard to distinguish between deliberate and accidental hits.

Attacks on power facilities, railways and data centres are all clearly part of a deliberate Russian strategy to make life as difficult as possible for civilians far from the slow-moving front lines.

With its long-range attacks on oil refineries and postal warehouses, Ukraine is doing something similar: bringing the war home to ordinary Russians.

But Russia's attacks on Ukraine's cities have intensified in recent weeks. Jet-powered drones are now more common than their slower predecessors, which used piston engines.

The latest Russian drones fly high and fast, making them harder to shoot down. There's also less time for civilians to react.

Kyiv is racing to develop low-cost weapons that can counter them as the missiles and fighter jets it has to fight back are too expensive.

In New York, Zelensky said, "we need ballistic interceptors to protect lives" and called on the US to help.

He said Putin needed to be stopped from continuing the war and "spreading this evil further", adding: "Putin is always looking for someone who can help him kill more, kill more people for every kilometre of land."

The Ukrainian president's comments came as Russian presidential envoy Kirill Dmitriev headed to the US to meet Trump administration officials, including Steve Witkoff and Jared Kushner, Reuters reported, citing two sources.

Russia's Lavrov told the UN Security Council on Wednesday there would be no pause in the war.

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