A dozen people were killed and about 50 injured in shootings across the United States over the weekend.

A family house party in South Jersey turned into a crime scene where at least two people were fatally shot and 12 others were wounded, state police said.

Authorities arrived at the house in Fairfield Township, about an hour outside of Philadelphia, late Saturday night. A resident who runs a local anti-violence organization said he was called out to assist families at the 90s-themed party. John Fuqua, of Life Worth Living, said guests who attended the party were of all ages.

New Jersey State police said a 30-year-old man and 25-year-old-woman were fatally shot. There were 12 other people who were injured and transported to local hospitals.

In another incident, at least three people were killed and three others were wounded in a shooting Sunday outside a bar in Youngstown, Ohio, police said.

Chief Carl Davis of the Youngstown police department said gunfire was reported shortly after 2 a.m. Sunday in the area of the Torch Club Bar & Grille in Youngstown.

Davis said three people were dead of apparent gunshot wounds and at least three others were wounded, one in critical condition.

None of the shootings occurred in the bar but they stemmed from an incident which began there, he said.

Arriving officers rendered first aid to victims near the establishment and officers from nearby departments were called in to help due to the large crowds in what he called a chaotic and tragic event.

Authorities said no one was in custody but they were talking to several individuals. Police declined comment on how many weapons were used or other details.

Police were processing evidence from two shooting scenes near the bar as well as a traffic accident reported at about the same time. It wasn’t immediately clear what relation the accident had to the shooting.

WKBN-TV reported dozens of casings in front of the bar as well as in a parking lot two doors down, where a house was also struck by gunfire.

Mayor Jamael Tito Brown said that, as a father of four, unnecessary violence involving young people just continues to pull at my heart.” It is not easy for me to get the call in the middle of the night from the chief or one of his team to tell me about incidents like this, and it pains me,” he said.

A 14-year-old girl was killed and 14 others wounded at an unauthorised outdoor concert Saturday night in North Charleston, South Carolina, officials said. The shooting occured at about 10:30 p.m. Saturday and found numerous victims with gunshot wounds.

“It’s a sad day that we have to be here today to talk about another death of another young person,” North Charleston Police Chief Reggie Burgess said during the press conference. “The individuals were angry at each other and they didn’t care who got hit,” he said.

The suspects have not been identified and a motive is not clear, although police suspect it was multiple gunmen that fired shots.

Two people were killed and eight more were wounded in a mass shooting in downtown Minneapolis early Saturday, police said. The dispute that began between two people led to the death of two males, whose names have not been publicly released. One of the injured is still in a critical stage while the rest have only non-life-threatening injuries, authorities said.

In another incident, a 16-year-old was shot to death and five other teenagers were wounded in mass shooting at Columbus Bicentennial Park Amphitheater in Columbus, Ohio, on Saturday night. Police and Columbus Fire medics who arrived at the scene found a chaotic scene with several people wounded.