An 8-year-old Ohio girl was shot dead over the weekend when “all hell broke out” at a teenager’s backyard birthday party, according to police and local reports.

Little Mikayla Pickett was struck in the back when gunfire erupted shortly before midnight Friday in the Sherbondy Hill neighborhood of Akron, cops said.

Willie Walker, 62, told the Akron Beacon-Journal that he was hosting a birthday bash for his 15-year-old grandson in his back yard when the shooting occurred.

“All hell broke out,” he said.

Three or four people showed up at the property and started firing at family members and friends who were at the celebration, said Walker, who was inside the house when the gunfire started.

He said he didn’t know the girl who died.

Police officers found multiple shell casings at the scene.

“I don’t know how many shells they took,” Walker said. “A lot of them.”

No arrests had been reported as of Sunday.

With Post wires