WARSAW (Reuters) -Poland’s president has declared a state of emergency in parts of two regions bordering Belarus, his spokesman said on Thursday, an unprecedented move in the country’s post-communist history that follows a surge in illegal migration.

The European Union has accused Belarusian President Alexander Lukashenko of using migrants from countries like Iraq and Afghanistan as part of a “hybrid war” designed to put pressure on the bloc over sanctions it has imposed on Minsk.

Poland has been trying to improve security along its frontier by building a fence and deploying troops.

“The situation on the border with Belarus is difficult and dangerous,” presidential spokesman Blazej Spychalski told a news conference. “Today, we as Poland, being responsible for our own borders, but also for the borders of the European Union, must take measures to ensure the security of Poland and the (EU).”

The Polish Border Guard said on Wednesday there had been around 3,500 attempts to illegally cross the border in August alone, 2,500 of which it had managed to thwart.

The government has also said it needs to be prepared for “provocations” that could transpire during military exercises organized by the Russian army that will be held on Russian and Belarusian territory near Poland from Sept. 10.

The “West-2021” drills will involve thousands of servicemen, including those from Kazakhstan, a member of the Moscow-led defense bloc, as well as tanks, artillery and aircraft.

“The second reason for bringing in the state of emergency in this area is the military exercises…that will take place on our border,” Polish Interior Minister Mariusz Kaminski said. “We must be prepared for every scenario.”

The state of emergency, which will restrict the movement of people and ban mass gatherings, is to apply to a 3-km-(1.9-mile)-deep swathe along the border for 30 days.

NGOs have sharply criticized the government’s approach to the issue and have said Warsaw must provide more humanitarian aid to migrants stranded on the border.

“This state of emergency is a nuclear solution that is to move us away from this border, not only us but also the media, and make sure that no one…will document what is happening there,” said Marianna Wartecka of the Ocalenie Foundation refugee charity.

Poland says the migrants are the responsibility of Belarus and it has also accused Minsk of refusing a convoy of humanitarian aid meant for them.

(Reporting by Alan Charlish, Pawel Florkiewicz, Alicja Ptak and Anna Koper; Editing by Mark Heinrich)