South Carolina authorities are investigating a shooting at a nightclub that left at least nine people injured.

The early Sunday mass shooting was the state's second and the third in the United States over the Easter holiday weekend.

At least 31 people were wounded in South Carolina and Pittsburgh shootings, where two youngsters were killed early Sunday.

According to an email from South Carolina's State Law Enforcement Division investigating the incident, no one was reported dead in the violence at Cara's Lounge in Hampton County, roughly 130 kilometers west of Charleston.

Two male teenagers were killed, and at least eight others were injured in Pittsburgh when shots were fired at a short-term rental apartment party.

According to police chief Scott Schubert, the "vast majority" of the party's hundreds of attendees were underage.

According to Mr. Schubert, investigators suspect there were numerous shooters, and police were processing evidence at up to eight separate crime scenes within a few blocks of the rented home.

The two shootings occurred less than a day after gunshots erupted at a busy mall in Columbia, South Carolina, approximately 145 kilometers north of Sunday's nightclub shooting.

Nine persons were shot, and five others sustained non-life-threatening injuries while fleeing the scene at the Columbiana Centre on Saturday, Columbia Police Chief W.H. "Skip" Holbrook said.

The victims ranged in age from fifteen to seventy-three. None of the victims sustained life-threatening injuries.

"We believe this was not an accident," Mr. Holbrook stated. "We believe they were acquainted and that something precipitated the shooting."

Jewayne Price, 22, is the only person arrested for the mall shooting thus far, and he was one of three people first detained by law enforcement as a person of interest.

Todd Rutherford, Price's attorney, told news outlets Sunday that his client discharged a gun at the mall, but only in self-defense.

Mr. Rutherford stated that Price faces a charge of unlawfully carrying a handgun because he legally owned his firearm but did not possess a permit to have one.

The three mass shootings over the Easter weekend are in addition to previous acts of gun violence in recent days.

A gunman opened fire in a New York subway car last week, hurting ten passengers. The following day, a suspect was arrested.

This month, six people were killed, and 12 others were injured in a shooting between rival gangs in Sacramento, California, as bars closed in a bustling downtown neighborhood only blocks from the state Capitol.

A week ago, a man and a woman were killed, and ten others were wounded in a shooting inside a busy nightclub in Cedar Rapids, Iowa.

And only last month, ten people were shot at a Dallas spring break party, and several others were hurt as they attempted to flee the shooting.