Romania’s Defense Ministry said early on Wednesday (24 July) that it scrambled fighter jets overnight as the Russian military carried out a series of drone attacks near its shared border with southern Ukraine.

The defense ministry said in a statement that two F-16 aircraft took off at 2:19 a.m. local time from the 86th Borcea Air Base, located around 126 kilometers east of the capital Bucharest. According to the statement, the fighter jets were tasked with monitoring “the aerial situation.”

Around the same time, Romania’s Tulcea County — which borders southern Ukraine’s Odesa region — was put on alert as Russian forces were said to have been carrying out drone attacks “against certain targets” near the NATO member’s border with Ukraine. Authorities did not specify where those attacks had taken place.

Since the start of Moscow’s full-scale invasion of Ukraine, Romania has on multiple occasions discovered drone debris near the border with its neighbor to the north. Authorities in the EU-member state have introduced measures to protect people living in and around the border area, including constructing air-raid shelters.