Two Russian fighter jets made an 18-second incursion into Lithuanian airspace on Thursday, the country’s armed forces said.

NATO jets were scrambled to intercept the aircrafts — an SU-30 and an IL-78 — which strayed 700 meters (0.4 miles) inside Lithuania’s airspace from Kaliningrad, Russia’s exclave on the Baltic Sea, the army said in an emailed statement. A Spanish-led air-policing unit continues to patrol the area of the incident, it said. 

Last month, three Russian fighter jets entered Estonian airspace in what the Baltic country called an unprecedented violation, triggering the North Atlantic Treaty Organization to hold talks amid accusations that Moscow was growing more brazen in testing the alliance.

Lithuania’s President Gitanas Nuseda called the incursion “a blatant breach of international law and territorial integrity of Lithuania. Once again, it confirms the importance of strengthening European air defence readiness.”