Prime Minister Donald Tusk says Poland is at its closest to open conflict since World War Two
He says up to four of 19 Russian drones were shot down by Polish and Nato aircraft, marking the first time Russian drones have been shot down over the territory of a Nato country
Poland's interior ministry says seven drones and the remains of an unidentified object have been found so far
The key question is whether this was a deliberate act by the Kremlin to test Nato's response, writes security correspondent Frank Gardner
The Kremlin says it won't comment. Earlier, a Russian diplomat in Poland rejected claims of drones in Polish airspace, state media reports
The drones that entered Poland were part of the latest major aerial attack on Ukraine, where Russia launched 415 drones overnight - President Volodymyr Zelensky calls it an "extremely dangerous precedent for Europe"
Vitaliy Shevchenko
Russia editor, BBC Monitoring
There's been complete silence so far from Russian officials.
But Russian state TV is quoting unnamed Polish members of parliament as saying this looks like a Ukrainian false-flag operation.
Sarah Rainsford
Eastern Europe correspondent, in Kyiv
Belarus and Russia are allies in the war on Ukraine.
Now, Pavel Muravyeika, deputy defence minister of Belarus, is claiming that the drones that entered Polish airspace did so accidentally, after their navigation systems were jammed.
In a video on the official defence ministry Telegram channel, he claims the drones "lost their way" and that Belarus itself had shot some down over its own territory.
He said between 23:00 and 04:00 local time (21:00 to 02:00 BST), his own forces, Poland and Lithuania had been sharing information through "communication channels" on the supposedly rogue drones.
Belarus is a dictatorship, it hosts Russian missiles. Russian troops entered Ukraine in 2022 through its territory. Its ties with Moscow are very close. So its words are not to be trusted.
But this may be the explanation Russia eventually gives for what Poland and EU officials - and Ukraine - are calling a deliberate violation of Polish airspace.
Frank Gardner
Security correspondent
Image source, ReutersThe key question here is: was this a deliberate act by the Kremlin to test Nato’s response?
To lose one drone over Poland’s airspace can be dismissed as an accident; it’s happened before.
But the incursion of "several drones", as reported by Poland, looks rather more deliberate.
To be clear, when we talk about drones in this context, these are not the little quadcopters that hunt down soldiers in trenches on the front lines with a grenade or artillery shell slung underneath.
These are much larger, pilotless aircraft packed with high explosive.
The Iranian-built Shahed-136, for example, measures 3.5m (11 feet) long by 2.5m (8.2 feet) wide. The Russian-made copies of these, the Geran-2, can carry a payload of anywhere between 30-50kg (66-110lb) of explosive, enough to smash into a residential block and kill or maim the inhabitants of several homes.
Every conversation I have had recently with Nato military officials or academic experts on what Russia’s next moves are likely to be all conclude that Moscow will want to test Nato’s resolve in some way.
Given Donald Trump’s apparent fondness for Vladimir Putin, there is some scepticism over whether his administration would actually come to the aid of a Nato member if they were attacked close to their borders.
Vitaliy Shevchenko
Russia editor, BBC Monitoring
The overnight Russian attack involved 415 drones, one ballistic and 42 cruise missiles, the Ukrainian air force says in its morning statement.
Of them, 386 drones and 27 cruise missiles were intercepted, it says.
"At least eight enemy UAVs crossed the Ukrainian state border flying in Poland's direction," the air force adds.
Vitaliy Shevchenko
Russia editor, BBC Monitoring
Polish residents earlier received the following SMS alerts on their phones: "Attention! Due to the operation to neutralise objects which have violated the border of the Polish Republic, inform services about drones and locations where they fall. Do not approach them."
The alert was sent by the Polish government's public safety account Alert RCB, external.
Adam Easton
Warsaw correspondent
Image source, ReutersPolish prime minister Donald Tusk has said the shooting down of Russian drones in Poland overnight was the first time this has happened in Nato territory.
Speaking ahead of an emergency government meeting, Tusk said Polish airspace was violated by a “huge” number of Russian drones.
He says that those which posed a threat were shot down by Polish and Nato pilots.
“This is the first time Russian drones have been shot down over the territory of a Nato country. All our allies are taking the situation very seriously. We have not recorded any casualties,” he says.
He adds that it was probably a “large-scale provocation” by Russia.
Tusk says the search for drones is ongoing, but he adds there is no reason to panic and the situation is now under control.
He says he is in contact with Nato’s secretary-general.
The Polish armed forces has now ended its military operation launched by the drone violations.
Airports, including the main international airport, Warsaw Chopin, have been reopened.
Adam Easton
Warsaw correspondent
Prime Minister Donald Tusk has said Polish airspace was violated by a “huge” number of Russian drones overnight.
Writing on X, Tusk says: “Those drones that posed a direct threat were shot down. I am in constant communication with the Secretary General of Nato and our allies."
More now from Ukraine's President Zelensky, who calls Russian drones entering Polish airspace "an extremely dangerous precedent for Europe".
"The Russians must feel the consequences. Russia must feel that the war cannot be expanded and will have to be ended," he says.
"The pause in sanctions has gone on far too long," he says, adding "a strong response is needed" from Ukraine's allies.
Image source, ReutersUkrainian President Volodymyr Zelensky says Russia's overnight drone attacks on his country show Moscow continues to "push the boundaries of what is possible".
Zelensky said the "massive" attacks killed one person in Zhytomyr region and injured three others in Volochysk where a sewing workshop was hit.
Fifteen regions were targeted overnight in an attack including "415 drones of various types and more than 40 cruise and ballistic missiles", he says.
"Moscow always pushes the boundaries of what is possible, and if it does not encounter a strong reaction, it remains at the new level of escalation," Zelensky says.
"Today there was another step of escalation – Russian-Iranian 'Shaheds' operated in the airspace of Poland, in Nato airspace. It was not just one 'Shahed' that could be called an accident, but at least eight strike drones aimed toward Poland."
Earlier this morning, Poland's Territorial Defence Force announced it would shorten the reporting time for soldiers.
The force, made up of professional and part-time volunteer soldiers, has asked soldiers in four eastern provinces to report within six hours if they received a request.
The change is in response to what the force calls a "violation of Polish airspace and the deployment of ground search and rescue teams".
Poland's fellow Nato members have issued statements expressing solidarity and concerns.
Swedish Prime Minister Ulf Kristersson said Russia's violations of Polish airspace were "unacceptable".
"The Russian war of aggression against Ukraine poses a threat to the security of all of Europe.
"Poland has every right to defend its airspace. We give our full support to Poland, as a Nato ally and EU member. Sweden and Poland stand united in our support for Ukraine," he said.
Latvian President Edgars Rinkēvičs posted expressed his "full support and solidarity" with Poland and its allies.
He said "Russian aggression in Ukraine affects us directly and appropriate measures must be taken".
Norway's Foreign Minister Espen Barth Eide also called Russia's move "deeply concerning and entirely unacceptable", reaffirming Norway's "steadfast support for our ally Poland and our shared commitment to European security".
Sarah Rainsford
Eastern Europe correspondent, reporting from Kyiv
Image source, EPAThis is a big test for Poland.
Its politicians talk a lot and loudly about the threat from Russia and the full-scale invasion of Ukraine has prompted a big boost in spending on its military.
In the past couple of years, I’ve seen children doing safety drills in Polish schools very similar to what I saw here in Kyiv in 2022, just before Russia attacked.
Ukraine is so close that people are acutely aware of the danger.
It’s even clearer when Russian aerial strikes focus on the west of Ukraine - like this time - and Poland scrambles its air forces on the border, to monitor the threat.
But they have never shot anything down before. That’s something that Ukrainians have often voiced frustration about - accusing Poland of being too cautious.
This time, the Polish air force has described the Russian drone incursion as an "act of aggression" - which is strong language - and the prime minister says he’s in "constant contact" with the head of Nato.
Adam Easton
Warsaw Correspondent
The Polish military also said in the statement that it thanked Nato's Air Command and the Netherlands for deploying F35 fighter jets in ensuring safety in Polish skies.
Ground-based air defence and radar reconnaissance systems have returned to standard operational activities, it added.
Adam Easton
Warsaw Correspondent
The Polish military has ended its military operation after it shot down drones that entered Polish airspace overnight.
Writing on X, it said: "The operations of Polish and allied aviation related to violations of Polish airspace have concluded. The search and localisation of possible impact sites of objects that violated Polish airspace are ongoing.
“With the safety of citizens in mind, we urge that in the event of observing an unknown object or its debris, do not approach, touch, or move it. Such elements may pose a threat and contain hazardous materials. They must be thoroughly inspected by the appropriate services."
Polish police say they found a damaged drone in Czosnówka, a village in eastern Poland, about 40km (25 miles) from the border with Belarus at 5:40am (4:40 BST).
"We have notified the appropriate services. Procedures are ongoing," police from the Lublin region said.
The airspace over Poland's major air hub, Chopin International Airport, has just reopened.
"The airspace over Warsaw Chopin Airport has been reopened," a post on X from the airport says.
As we reported earlier, the airport was open but no flights were in operation due to Polish military activities against suspected Russian drones.
The incursion into Polish airspace occurred during Russia's overnight drone attack on Ukraine.
Here are some pictures from Kyiv overnight, showing explosions in the night sky as Ukrainian servicemen fire at drones:
Image source, Reuters
Image source, Reuters
Image source, ReutersAn extraordinary meeting of the Council of Ministers will be held in the next hour.
A spokesperson from the Polish government says the meeting will take place at 8am local time (7am BST), adding that Polish PM Donald Tusk is already meeting with ministers responsible for state security.
The time is now 7am in Warsaw, or 6am BST. If you're just joining us, here's what's been happening overnight: