Romania shot down a suspected Russian drone after it entered the country’s airspace on Sunday, marking the third such incursion in three days for the Eastern European state, which is both a European Union and NATO member, President Nicusor Dan said.

NATO said two Romanian F-16 fighter jets were scrambled from the Fetești airbase under the alliance’s operational command and shot down the drone over the Black Sea.

“A new drone was shot down this morning, at 10:13, by an F-16 aircraft of the Romanian Air Force, over the territorial waters of Romania, in the Sulina–Chilia area,” Dan said.

The Sulina–Chilia area lies in the Danube Delta region near Romania’s border with Ukraine, a stretch that has repeatedly drawn attention since Russia began targeting Ukrainian ports and infrastructure along the Danube and the Black Sea.

The president said authorities had determined that one of the previously intercepted drones appeared to be “a Shahed type, used by the Russian Federation in the war of aggression against Ukraine.”

Col. Martin O’Donnell, a spokesperson for NATO’s Supreme Headquarters Allied Powers Europe, known as SHAPE, said the incident was the fourth recent downing by Romania of a drone violating NATO airspace in coordination with the alliance.

Before the latest three interceptions, Romanian jets shot down a drone in the sky above Estonia in May, O’Donnell said. Romanian pilots and aircraft are stationed in Lithuania, where they have broad strike capabilities as part of NATO’s force posture.

“As we continue to prove, NATO is constantly on the watch and prepared to defend itself from any threat,” O’Donnell said.

Romania’s response comes as NATO has put more emphasis on air policing, surveillance and counter-drone defenses along its eastern flank, where alliance members border Ukraine, Belarus or Russia and have had to manage the risk of unmanned aircraft crossing into allied airspace.

Romania has acquired the MEROPS counter-drone system, which launches relatively low-cost, three-foot-long drones designed to take down incoming Shahed drones and other variants. The system is part of a broader effort across NATO to strengthen the alliance’s long eastern border against drone threats.

In May, a Russian drone that was part of an attack on Ukraine went off course and hit an apartment building in eastern Romania, injuring two people and increasing concerns that the war could spill into NATO territory.

“It is inadmissible and intolerable that the Russian Federation continues to violate Romanian airspace, which is also NATO and European Union airspace,” Dan said. “Such actions are unacceptable and we treat them with all seriousness, together with our allies.”

Belgium, also a NATO and EU member, said Sunday’s incursion was a “stark reminder of the ongoing threat Russia’s war poses to European security.”

“Belgium stands firmly with Romania after several drones were shot down over its territory in the past days. Romania’s investigation has already confirmed that one of them was a Russian Shahed drone,” Belgian Foreign Minister Maxime Prévot said. He added that 300 Belgian troops are based in Romania as part of NATO’s eastern flank force.

Drone incursions by Russia and Ukraine have affected Romania and other NATO members since Moscow launched its full-scale invasion of Ukraine in February 2022.