(CNN) -- A federal prosecutor will review the case of a Georgia SWAT team that threw a flash-bang grenade into a playpen, according to a Tuesday statement.
The news comes a day after a state grand jury declined to return an indictment.
The incident, which severely injured a 1-year-old child, occurred in May when the Habersham County Special Response Team conducted a drug raid in Cornelia. The grand jury began hearing the case late last month.
"Federal authorities have been participating in the investigation of this terrible incident, and now that a state grand jury has declined to return an indictment, we will review the matter for possible federal charges," said U.S. Attorney for the Northern District of Georgia Sally Quillian Yates.
The police officers involved were called baby killers and received threats following the incident, Habersham County Sheriff Joey Terrell said at the time.
The SWAT team, made up of six or seven officers from the sheriff's department and the Cornelia Police Department, entered the Cornelia residence of Wanis Thonetheva on the morning of May 28.
A confidential informant hours earlier had purchased methamphetamine at the house, the sheriff said.
Because Thonetheva had a previous weapons charge, officers were issued a "no-knock warrant" for the residence, Terrell said.
When the SWAT team hit the home's front door with a battering ram, it resisted as if something was up against it, the sheriff said, so one of the officers threw the flash-bang grenade inside the residence.
Once inside the house, the SWAT team realized it was a portable playpen blocking the door, and the flash-bang grenade had landed inside where a 19-month-old was sleeping, the sheriff said.
A medic on the scene rushed the baby outside to administer first aid, and a nearby ambulance transported the baby to a hospital.
The child's mother, Alecia Phonesavanh, told CNN affiliate WSB the family was sleeping at her sister-in-law's house when police arrived, and the grenade seared a hole through the portable playpen after exploding on the child's pillow.
"He's in the burn unit. We go up to see him and his whole face is ripped open. He has a big cut on his chest," Phonesavanh told the station at the time.
Thonetheva, 30, was not at the home at the time of the raid, but the toddler's mother and father and their other three children were inside. Thonetheva's mother was also at the house, Terrell said.
Thonetheva was arrested at another Cornelia residence, along with three other people, shortly after the raid, Terrell said. He was charged with distribution of methamphetamine.
Thonetheva was not charged with any weapons crime, and as for drugs, Terrell said officers found only residue in the home.
In hindsight, Terrell said at the time, officers would've conducted the raid differently had they known there was a child inside the home, but there was no sign of children during the alleged drug purchase that prompted the raid.
"We might have gone in through a side door," he said. "We would not have used a flash bang."