A small fire Thursday night outside the Lawrence Community Shelter resulted in plenty of smoke inside the building at 214 W. 10th St.
Fire crews went to the center shortly after 8 p.m. on a call about smoke in the building.
When firefighters arrived, they found smoke in the basement, but later discovered that a small fire outside a basement vent had drawn smoke into the building.
A group of about 40 homeless people had to leave the building.
Don Huggins, president of the Lawrence Community Shelter, said they would be able to return to stay the night after fire crews ventilated the building.
Joe Hoelscher, division chief for Lawrence-Douglas County Fire & Medical, said one person was treated at the scene for smoke inhalation.
He said he believed there was nothing suspicious about the fire.