Authorities on Tuesday investigated an explosion near a building housing a chapter of the NAACP civil rights group in Colorado Springs.
Police and the FBI responded to the blast and were at the location of the National Association for the Advancement of Colored People chapter, police and FBI representatives said.
A woman who answered the phone at the NAACP office but declined to give her name said people inside the building heard a "loud boom" coming from a lawn area in the rear.
The Colorado Springs Gazette reported that there were no injuries in the blast near the building, which also houses a hair salon. Streets around the area were closed while authorities investigated, the newspaper said.
The FBI is looking a White man, balding in his 40s. According to reports, this man may know about the homemade explosive.
More to come on this story.