A photo of 19-month-old Bounkham Phonesavanh who was severely burned by a flash grenade during a SWAT drug raid, is held by a supporter during a vigil outside Grady Memorial Hospital where he is undergoing treatment, Monday, June 2, 2014, in Atlanta. A Georgia state senator says he will ask U.S. Attorney Sally Quillian Yates to investigate a police raid where the Georgia toddler was severely burned by a flash grenade. State Sen. Vincent Fort joined 19-month-old Bounkham Phonesavanh's family at a prayer vigil outside Grady Memorial Hospital in Atlanta on Monday. The boy's mother says a fever may delay a planned surgery. Police have said officers were looking for a suspect who may have been armed and didn't know children were inside. (AP Photo/David Goldman)

By David Beasley

ATLANTA, Oct 6 (Reuters) - A grand jury in Georgia on Monday declined to indict sheriff's deputies who during a drug raid in May set off a stun grenade that severely injured a 19-month-old boy, prosecutors said Monday.

The toddler, Bounkham Phonesavanh, was badly burned when the "flash-bang" device landed in the playpen where he was sleeping during a raid to arrest a suspect police say had sold methamphetamine to an undercover officer in northeastern Georgia.

A federal investigation of the incident is still pending, Habersham County District Attorney Brian Rickman said.

County Sheriff Joey Terrell has called the boy's injuries "devastating" but unavoidable, saying police who tossed the grenade to distract the suspect did not believe children were in the home.

The suspect, a relative of the child, was not in the house during the raid but was later arrested nearby, police have said.

Rickman decided to let the grand jury decide whether to bring state criminal charges against the officers.

The grand jury concluded the deputies did not intentionally injure the child and were not criminally negligent, Rickman said. But the grand jurors did issue a 15-page report suggesting how to prevent a similar tragedy from occurring again.

"Basically, they recommended that these types of SWAT entries into homes be done only when it's absolutely necessary," the district attorney said.

A recent report by the American Civil Liberties Union found that nearly 80 percent of police raids carried out by heavily armed Special Weapons and Tactics (SWAT) units - originally designed for emergencies like hostage takings and active-shooter situations - were being used to serve search warrants, usually in drug cases.

The child's relatives are unhappy with the grand jury's decision, said their attorney, Mawuli Davis.

The Habersham County Board of Commissioners has said the law prevents the county from paying the toddler's medical expenses.

Davis said he knows of no legal barriers to payment of the bills, which he said exceed $800,000. (Editing by Jonathan Kaminsky, Steve Gorman and Eric Walsh)