Poland has announced temporary air restrictions in its eastern region following a series of drone incursions that violated its airspace on Wednesday.

The Polish Air Navigation Services Agency (PAZP) said on Thursday that civilian flights will be barred up to an altitude of three kilometres (1.9 miles) in areas stretching 26 to 46 kilometres from the border with Belarus and Ukraine. The restrictions, which include a total ban on drone activity “day and night,” will remain in place until December 9.

Officials said the measures were necessary “to assure national security.”

On Wednesday, Polish authorities reported that the country’s airspace was breached 19 times, with at least three drones shot down as Polish and allied jets scrambled in response.

NATO confirmed its forces played a role in countering the incursion. Alliance spokeswoman Allison Hart said in a statement that “numerous drones entered Polish airspace overnight and were met with Polish and NATO air defences,” adding that Secretary General Mark Rutte was in contact with Warsaw.

US General Alexus Grynkewich, NATO’s top commander in Europe, described the alliance’s response as “quick and decisive,” noting it was the first time NATO aircraft had engaged potential threats in allied airspace.

According to the alliance, Dutch fighter jets were dispatched to engage the drones, while German Patriot air defence systems in Poland were placed on alert and an Italian early warning aircraft was launched.

“NATO is committed to defending every kilometre of NATO territory, including our airspace,” the statement read.