The U.S. Embassy in Oslo, Norway, was struck by an explosion early Sunday morning, causing minor damage.

Police officers and emergency services responded to the scene shortly after the incident occurred around 1 a.m. local time. Oslo police stated they had no information about the cause of the blast or who was responsible.

“A loud bang/explosion was reported at the scene,” police said.

Police incident commander Michael Delmer confirmed that the blast struck the entrance to the embassy’s consular section. “At around 1 a.m., we received several reports of an explosion. We arrived shortly afterward and confirmed there had been an explosion that hit the U.S. embassy,” he told reporters.

Delmer added, “We are not going to comment on anything related to the type of damage, what exploded, or similar details because it is very early in the investigation.”

The police also stated they were in contact with the embassy and no injuries had been reported. A 16-year-old resident who lives nearby told local television that he heard a loud blast while watching TV at home. “My mother and I first thought it came from our house so we looked around, but then we saw flashing lights outside the window and a ton of police,” he said.

He described seeing police dogs, drones, armed officers with automatic weapons, and helicopters in the air. Local reports indicate a heavy police presence at the embassy, with images from the scene showing police vehicles and armed officers surrounding the building.