Constanta county prefect Adrian Teodor Picoiu was quoted by news website www.g4media.ro saying that Ukraine had notified Romania that the maritime drone which exploded in the Black Sea port of Constata on Friday was part of group of five. He added that one drone exploded in Constanta, another in Ukraine, and a search was ongoing for the remaining three, the website said. The Romanian port was evacuated and residents along Romania's Black Sea coast were warned to take cover. "We now know there is the risk of self-detonation, we have ... evacuated in case there are more drones," deputy Interior Minister Raed Arafat sai "We are not panicking, the measures are purely preventative." According to Romanian news channel Digi24, three more maritime drones were found on Romanian coast after explosion in Constanta port. The explosion comes a week after a Russian drone crashed into an apartment building in the southeastern Romanian city of Galati, near the border with Ukraine, injuring two people - the first time in the Russia-Ukraine war that a drone struck a densely populated area in a NATO state. Romania, a NATO and European Union member, shares a 650-km (400-mile) border with Ukraine and has reported 28 incursions into its airspace by Russian drones since Moscow began attacking Ukrainian ports on the Danube, the defense ministry has said. Ukrainian drone fragments have also landed on Romanian territory.