A fast-moving wildfire threatened structures in Utah County and temporarily shut down a stretch of highway.

The blaze started about 4 p.m. Wednesday near Cedar Fort, a town of about 400 people to the west of Utah Lake. By 9 p.m., crews said, the fire had grown to 209 acres.

Firefighters responded to the area with two airplanes to try to control the flames from above as high winds pushed it forward.

Highway 73 was closed for a few hours as they worked to battle the blaze. It was 50% contained by night’s end.

It wasn’t immediately clear how many structures were threatened, but residents were let back into the area. Investigators said Wednesday that they determined it was human-caused; they did not offer details.