A man with an assault rifle and other weapons exchanged gunfire with officers at a school in the southern US state of Georgia before surrendering, a police chief has said.
Dramatic overhead television footage on Tuesday showed the young pupils racing out of the building, being escorted by teachers and police to safety. No-one was injured.
Just a week into the new school year, more than 800 students in pre-kindergarten to fifth grade were evacuated from Ronald E. McNair Discovery Learning Academy in Decatur, a few miles east of Atlanta.
They sat outside along a fence in a field for a time until school buses came to take them to their waiting parents and other relatives at a nearby Wal-Mart supermarket. When the first bus arrived about three hours after the shooting, cheers erupted in the store car park from relieved relatives, several of them sobbing.
The suspect, identified later as 20-year-old Michael Brandon Hill, fired at least a half-dozen shots from the rifle from inside McNair at officers who were swarming the campus outside, police said. Officers returned fire when the man was alone and they had a clear shot, DeKalb County Police Chief Cedric Alexander said at a news conference.
Hill surrendered shortly after and several weapons were found, Mr Alexander said. Police had no motive. Though the school has a system where visitors must be buzzed in by staff, the gunman may have slipped inside behind someone authorised to be there, Mr Alexander said.
The suspect, who had no clear ties to the school, never got past the front office, where he held one or two employees captive for a time, the chief said. Hill is charged with aggravated assault on a police officer, terroristic threats and possession of a firearm by a convicted felon.
A woman in the office called WSB-TV to say the gunman asked her to contact the Atlanta station and police. WSB said during the call, shots were heard in the background. Assignment editor Lacey Lecroy said she spoke to the woman who said she was alone with the man and his gun was visible. "It didn't take long to know that this woman was serious," Ms Lecroy said. "Shots were one of the last things I heard. I was so worried for her."
School clerk Antoinette Tuff said in an interview with TV station ABC that she worked to convince the gunman to put down his weapons and ammunition. "He told me he was sorry for what he was doing. He was willing to die," she told ABC. She told him her life story, about how her marriage fell apart after 33 years and the "roller coaster" of opening her own business. Then she said she asked the suspect to put his weapons down, empty his pockets and backpack on the floor. "I told the police he was giving himself up. I just talked him through it," she said.
DeKalb County Schools Superintendent Michael Thurmond praised staff and authorities who got the young students to safety, staying calm and following plans in place. All teachers and students made it out of the school unharmed. Complicating the rescue, bomb-sniffing dogs alerted officers to something in the suspect's car and investigators believe the man may have been carrying explosives.