Construction workers say sparks from their equipment may have set the roof on fire this afternoon in downtown Des Moines.
It happened around 2:00pm on the east side of 5th Street between Center St. and Park Street where a new building is being completed.
Workers said they noticed smouldering insulation, then saw flames from the roofing materials.
Fire crews blocked off 5th Avenue and used their ladder truck to put out any flames. Crews remained on the roof for over an hour to make sure there weren't any flareups.
The construction workers were able to leave the roof without incident. Noone was injured.