ATLANTA (AP) — Federal authorities and police are investigating after four Confederate battle flags were found on the grounds of the Ebenezer Baptist Church near the Martin Luther King Jr. Center in Atlanta.

Officer Gary Wade says a maintenance worker discovered the flags at 6 a.m. Thursday and notified the National Park Service, which operates the nearby King Center. Wade says no one saw who placed the flags, which weren't stuck in the ground but instead set neatly on top of it. He says there's at least one security camera for the area. Authorities are reviewing footage.

Wade says a security guard saw a suspicious vehicle across the street from the church Wednesday night, but it wasn't clear whether that was related.

King once preached at the historic Ebenezer Baptist Church, which is near the new church where the congregation now meets and where the flags were placed.