Addressing the country’s parliament, Prime Minister Donald Tusk said that while there was no reason to say that Poland was in a state of war, it was closer to a conflict than any time since World War II.

He said Poland was facing an “enemy that does not hide its hostile intentions.”

Tusk also announced that Poland has invoked Article 4 of NATO, meaning the military alliance’s main political decision-making body will meet to discuss the situation and its next steps.

NATO’s Secretary General Mark Rutte said that the violation of Poland’s airspace was “absolutely reckless” and not an “isolated incident.”

Tusk said there were 19 intrusions of his country’s airspace, and that a “large proportion” of the drones entered it from Belarus.

He called the incident an “unprecedented violation of (its) airspace” and said it lasted all night – from just before midnight local time on Tuesday until 6.30am on Wednesday (Wednesday evening AEST).

Poland’s interior ministry said seven drones and parts of one unidentified missile have been found.

The locations where the debris was found span the area of hundreds of kilometres.

The ministry’s spokesperson Karolina Gałecka said that one of the drones hit a residential building in the village of Wyryki, in eastern Poland, near the border with both Ukraine and Belarus.

Photographs from the scene geolocated by CNN show extensive damage to a family house there.

No injuries were reported, according to Polish media.

Another piece of a drone was discovered near a cemetery in Cześniki in Zamość County, some 100 kilometers south of Wyryki, according to a statement from the local prosecutor’s office.

Tusk said it was the first time Russian drones had been shot down over the territory of a NATO member state and the incursion involved a “huge number” of them.

“We are most likely dealing with a large-scale provocation,” Tusk said on Polish television, following an emergency meeting of the country’s National Security Bureau.

He said the “situation is serious” and that Poland was “ready to repel” this type of attack.

“The security of our homeland is our highest priority,” Polish President Karol Nawrocki said.

Allies react and a search for downed drones

Poland is a member of NATO, the transatlantic defence pact involving the United States that employs the principle that an attack on one is an attack on all.

European faith in the reliability of that alliance has been shaken under US President Donald Trump who, alongside key cabinet members, have called on Europe to lead in its own defence.

Rutte said he has been in touch with the Polish leadership and that NATO itself was “closely consulting” with Poland.

He said the response by the alliance was “very successful” and showed that NATO was able to, and will, defend “every inch” of its territory.

The European Union’s foreign policy chief, Kaja Kallas, called the incident “the most serious European airspace violation by Russia since the war began.” Kallas said that the “indications suggest it was intentional, not accidental,” adding that: “Russia’s war is escalating, not ending.”

The Polish military thanked NATO member the Netherlands for contributing F-35 fighter jets to defensive operations overnight, which have now concluded.

Ukraine’s President Volodymyr Zelensky said at least eight “Shahed” drones had been aimed toward Poland, in what he called “an extremely dangerous precedent for Europe.” His own country endured a Russian attack involving 415 drones and 40 missiles overnight.

The leader of the newest NATO member, Sweden, called the presence of Russian drones over Poland “unacceptable.”

“The Russian war of aggression against Ukraine poses a threat to the security of all of Europe,” Swedish Prime Minister Ulf Kristersson said in a post on X.

“Russia is deliberately expanding its aggression, posing an ever-growing threat to Europe,” said Gitanas Nauseda, the president of Lithuania, also a NATO member.

The incursion comes as Trump’s attempts to strike a peace deal between Russia and Ukraine have ground to a halt, with Moscow only scaling up its aerial assaults.

Ukrainian Foreign Minister Andrii Sybiha said Russian President Vladimir Putin is “testing the West.”

“Russian drones flying into Poland during the massive attack on Ukraine show that Putin’s sense of impunity keeps growing,” Sybiha said in a post on X.

Ned Price, a US State Department spokesperson during the Biden administration, also thought Russia may have sent drones over Poland to test NATO resolve and defenses.

While cautioning it could be the case that the drones flew over Poland by mistake or because of Ukrainian countermeasures, Price told CNN’s Laura Coates their presence, if deliberate, could expose what Russia might see as “weakness.”

US Sen. Dick Durbin, an Illinois Democrat, was more direct.

“Repeated violations of NATO airspace by Russian drones are fair warning that… Putin is testing our resolve to protect Poland and the Baltic nations,” Durbin said in a post on X.

Polish Defence Minister Wladyslaw Kosiniak-Kamysz said Territorial Defence forces had been activated to search for downed drones.

He urged people to “remain calm” and said anyone who found fragments of military equipment should report it to authorities.

Earlier, authorities closed airspace over Warsaw International Airport and other smaller airports “due to unplanned military activity related to ensuring state security,” according to a Notice to Airmen (NOTAM) posted on the US Federal Aviation Administration’s website.

The Warsaw airport reopened Wednesday morning, Mayor Rafal Trzaskowski said in a post on X.

Putin emboldened after China parade

Since then, Russia has staged its largest aerial assaults on Ukraine since it fully invaded its neighbour more than three years ago.

The recent attacks have largely targeted residential areas around the country and in the capital of Kyiv.

On Tuesday, 24 civilians were killed in a Russian strike on the village of Yarova in the eastern Donetsk region, Ukrainian officials said.

The attack hit the Cabinet of Ministers building, which houses the prime minister’s office, as well as some government ministries.

Any progress made has long since evaporated with Russia’s expanded aerial attacks.

Poland earlier announced it was closing its eastern border with Russian ally Belarus, due to joint Russian-Belarusian military exercises beginning on Friday, Reuters reported.

The Zapad 25 large-scale exercises, which will take place in western Russia and Belarus, have raised security concerns not only in Poland but also in the neighbouring NATO countries on Lithuania and Latvia, according to Reuters.

“On Friday, Russian-Belarusian maneuvers, very aggressive from a military doctrine perspective, begin in Belarus, very close to the Polish border,” Prime Minister Tusk told a government meeting, Reuters reported.

“Therefore, for national security reasons, we will close the border with Belarus, including railway crossings, in connection with the Zapad maneuvers on Thursday at midnight,” Tusk said.