Firefighters battle fire at 50th and Capitol in Milwaukee

MILWAUKEE (CBS 58) -- Fire crews rushed out Friday morning to battle a fire on Milwaukee's north side. 

It happened around 5:00 a.m. at a building near 50th and Capitol. 

Authorities say the building is an H-VAC supply store on the first level and people live on the second level, so there was a concern for people sleeping. When crews checked the building, they did not find anyone inside. 

Investigators say the fire started on the first floor and was quickly knocked down. They are trying to figure out the cause. 

No one was hurt in the fire.