A sea drone has reportedly exploded in the port of Constanta, which is the largest coastal and port city in Romania.
The blast happened at around 10.30am EEST (8.30am UK time), local media report.
Police, border guards, paramedics and firefighters are among the emergency services at the scene. A Black Hawk helicopter has also mobilised to provide support, according to Romania’s Department for Emergency Situations (DSU).
The surrounding area has been cordoned off and people have been evacuated.
There were no reports of injuries, according to DSU spokesman Bogdan Toma.