ATLANTA (CNN) -- It started as a helicopter search for a missing 9-year old boy. About two hours later, the police chopper lay in pieces on a city street, two officers were dead and hundreds of northwest Atlanta residents had no power.

The helicopter with two officers on board crashed late Saturday night, just miles from downtown. It was flying low to enable the officers to conduct a more thorough search, according to Atlanta Police Chief George Turner.

Both officers died on impact.

On Sunday afternoon, the police department identified the officers as 48-year-old Richard Halford and 40-year-old Shawn Smiley.

Halford, who joined the force in 1986 and had been with its air unit the past 16 years, is survived by his former wife and a 21-year-old daughter. Smiley leaves behind his wife and three children -- ages 5, 7 and 9 -- and had joined the Atlanta police department in 2010.

"Losing an officer is the most difficult thing a police chief can face," Turner said. "Losing two is an unthinkable tragedy. Our hearts go out to the families of these officers and our thoughts and prayers are with them. This is a difficult day ... it is a reminder of their bravery and the sacrifices made by our officers every day."

The late officers were among those responding to a call about a missing boy, made shortly before 9 p.m. Saturday. Witnesses saw the police helicopter, which was being used to look for the child, lose control and crash into the street about an hour and a half later, according to police.

There were no injuries on the ground, but the crash knocked out power to 1,300 Georgia Power customers.

The Federal Aviation Administration and the National Transportation Safety Board are investigating.

Turner said his department has cordoned off the area, but has turned the investigation over to the federal authorities.

The missing boy was later found safe.

CNN's Maggie Schneider and Ayana Smith contributed to this report.

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