Masked gunmen fired without warning into a crowd at a late night teen party at a South Carolina park over the weekend, wounding nine people, a sheriff said.

All nine hit by gunfire are expected to live, as well as a woman who was injured when she was run over by a fleeing car and another person who was cut on the hand, Richland County Sheriff Leon Lott said in a Sunday update on the Saturday shooting.

“So fortunate and so glad and so thankful that right now we believe that everybody is going to survive,” Lott said. “It’s not because those who were doing the shooting didn’t try.”

Deputies were called to Meadowlake Park near Columbia around 1:20 a.m. Saturday and found only a few people at the scene. Not long after, hospitals started reporting several gunshot victims arriving in emergency rooms, deputies said.

Teenagers from several high schools had gathered at the park for the afterhours “flash party” that was announced on social media and not sponsored by the local recreation commission, Lott said.

“This was people putting it out on social media and saying, ‘Come,’ and the bad people came,” the sheriff said.

The shooting appeared to be unprovoked, Lott said.

“If you think wearing a mask, sneaking around a building and shooting into a crowd makes you a man — no, you are a coward,” the sheriff said,

Many of the wounded were hit in the back as they tried to run away, Lott said.

Dozens of shell casings from several different weapons have been collected at the park. Lott said Sunday that multiple people were firing guns at the park where teens had gathered and that some of those guns were automatic.

The people injured are between the ages of 16 and 20. Lott said some were undergoing surgery Sunday.

Officers arrested two teenagers in a vehicle driving away from the scene with its headlights off and found a gun tossed from the vehicle, but Lott said investigators are still trying to figure out if it was used in the shooting.

Lott said he expects his deputies will be making other arrests soon.