Poland launched a major security operation this week along its border with the Russian enclave of Kaliningrad, according to Poland's national police chief. 

Polish and allied intelligence agencies had warned of potential sabotage operations and provocations during the first half of November. The possible actions include border incursions by armed groups, CBS News reported. 

Prime Minister Donald Tusk said Tuesday that suspicious movements were observed overnight near Kaliningrad, which includes individuals carrying flashlights close to the border area.

The quick reaction by Polish security forces, Tusk said, may have prevented an unspecified provocation. 

Kaliningrad is considered to have military and strategic significance, and it's widely believed that Russian security agencies, including the FSB and GRU intelligence agencies, have a presence in the territory.