Poland has deployed counterterrorism police near its border with Russia’s Kaliningrad exclave following warnings of possible sabotage in the coming days, broadcaster TVP World reported Monday.

Police chief Marek Boron said a special police-led operation was underway in the northeast, involving the military, border guards and intelligence services.

A large group of officers, including personnel transferred from other provinces and counterterrorism units, had been deployed, he told private broadcaster RMF FM.

Police were securing the border area “in light of possible events that could lead to acts of sabotage,” Boron said.

“It is based on information that was also provided by external agencies. We have to ensure the safety of citizens who live there but also of facilities and of a whole range of situations which could endanger society.”According to security sources cited by Polish broadcaster RMF FM, Poland received warnings last week from its Military Intelligence Service and allied intelligence agencies that armed groups could attempt to cross the border from Russia in the coming days.

Police also denied speculation that an instruction requiring provincial commanders to remain at full readiness from Nov. 2-8 was linked to tensions surrounding Poland’s Constitutional Tribunal. The readiness order concerned sabotage threats, police said in a social media statement.

Kaliningrad, a Russian exclave on the Baltic Sea, borders Poland and Lithuania, both NATO members.

The nearby Suwalki Gap, a narrow stretch of territory separating Kaliningrad from Belarus, is considered strategically important because it connects the Baltic states with other NATO allies by land.