A suburban Atlanta police department is mourning the death of one of its officers, gunned down as he helped other officers serve a `no knock' warrant in a drug case.

Riverdale Police Chief Todd Spivey said Maj. Greg Barney, a 25-year veteran, died following surgery after Thursday's shooting.

Clayton County Police Chief Michael Register tells The Atlanta Journal-Constitution that Barney was shot while helping Clayton officers serve the `no knock' warrant at apartments in Riverdale, south of Atlanta's airport. Authorities say a suspect, who wasn't identified, was wounded.

A wreath was left outside the Riverdale police headquarters. WSB-TV showed images of two candles glowing outside the police department's entrance. At a nearby church, Frances Lee said a message was being put on the sign: "Our prayers are with the Barney family."

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