Flames from an explosion at a home in Portland's Northwest Hills spread to a neighboring house late Thursday morning., Portland Fire & Rescue said.

PF&R was originally called to a home at the 10400 block of Burkhardt Court in the NW hills on a report of an explosion.

Crews from Portland Fire and Tualatin Valley Fire & Rescue arrived shortly before 10:30 a.m. to find a house engulfed in flames, with the fire spreading to a neighboring home.

The incident was upgraded to a second alarm, bringing in more resources.

The fire was out shortly after 11 a.m., but the scene was still active and crews stayed at the scene to investigate what caused the explosion and subsequent fire.

There were no known injuries reported.

NW Natural is also on-scene to ensure gas service is secure.