Update: As of about 6:20 a.m. local time (05:20 UTC) on March 8, police say there have been no major developments in the investigation into the blast at the U.S. Embassy in Oslo. Authorities have appealed for public tips, while reiterating that no one was injured and the damage was limited to the consular entrance. The large police response remains in place, but officials continue to say the situation is stable, contained, and poses no immediate danger to the public.

A blast struck the entrance to the consular section of the U.S. Embassy compound in Oslo early Sunday, damaging the entryway and sending heavy smoke into the air, but causing no reported injuries, according to Norwegian authorities and local media.

The explosion happened at about 1:00 a.m. local time at the embassy complex in Huseby, western Oslo. Police said the damage appears to be limited to the consular entrance, while emergency teams, bomb technicians and forensic investigators continue working at the scene. Authorities have not said what caused the blast, who may be responsible, or whether the incident was targeted.

By around 2:30 a.m. local time, police incident commander Michael Dellemyr said investigators had formed an idea of what caused the explosion but were withholding that information for investigative reasons. Officers were still searching the surrounding area with dogs, drones and helicopters to rule out any additional threat and to look for possible perpetrators.

The response remained extensive through the early morning hours. Sørkedalsveien was closed, and police established a security cordon of roughly 700 meters around the embassy, with vehicle checkpoints and inspections in place.

Residents near the embassy told VG they were jolted awake by a powerful bang. One witness said the explosion was strong enough to shake nearby homes, and that heavy smoke could be seen rising from the embassy grounds.

Police said they remain in direct contact with embassy officials. As of the latest update, neither the U.S. Embassy in Oslo nor the U.S. State Department had issued a public statement. The embassy’s website also showed no security alerts, closures or disruptions to normal operations.

Authorities have so far linked the investigation to no broader event, and no suspects, motive or attribution have been announced. Police say this remains the only confirmed incident.

The investigation is ongoing, and more information is expected as Norwegian authorities continue examining the scene in the hours ahead.