NATO member Romania said on Friday that a drone injured two people in a southeastern city during an overnight Russian attack on neighboring Ukraine, the ‌first time in the war that a drone had hit a densely populated area in Romania and caused injuries, Reuters reported citing local authorities.

The drone hit the roof of a 10-storey block of flats in Galati and caused an explosion, the authorities said.

Romania, which shares a 650-km (400-mile) land border with Ukraine, has experienced Russian drones breaching its airspace 28 times since Moscow began attacking Kyiv’s ports across the Danube river, Romania’s ⁠defense ministry said.

The ministry said it had recovered drone fragments that fell in Romania 47 times.

“Romania will take the necessary diplomatic measures in response to this serious violation of international law and its airspace,” Romanian Foreign Minister Oana Toiu said on X.

“Romania has informed the Allies and the NATO Secretary General of the circumstances and has requested measures to accelerate the transfer of anti-drone capabilities to Romania.”

The defense ministry said it scrambled two F-16 fighter jets and a military helicopter to monitor the attack, adding the pilots were authorized to shoot down any drones. The residents of border counties Braila, Galati and Tulcea were warned to take cover.

Romanian law allows it to shoot down drones during peacetime if lives or property are at risk, but it has not yet done so.

In Friday’s incident, a fire broke out in a 10th-floor apartment after ‌the drone ⁠struck the building’s roof and exploded, Romania’s emergency response agency said. Two people were receiving medical treatment on site, it said, adding 70 people had evacuated.