Slidell police have arrested three cousins in a shooting last month that seriously wounded a 26-year-old man who was trying to help a homeowner bring a college acceptance party to an end.

Tyrone Ward, 21, was booked with attempted second-degree murder, and Michael Harris, 24, was booked with being a principal to attempted second-degree murder. Ashley Brandon, 17, was booked as an accessory after the fact to attempted second-degree murder.

The shooting happened at about 2 a.m. July 20. Police arrived to find 26-year-old Jamar Wilson lying in a driveway near Daney and 10th streets with multiple gunshot wounds, Slidell Police Department spokesman Daniel Seuzeneau said in a news release.

The victim was taken to Interim LSU Hospital in New Orleans, where he is still listed in guarded condition, the release said.

Slidell police spent a week and a half interviewing witnesses. “Our detectives have spent hundreds of man-hours identifying and putting together a strong case against those responsible for this senseless act of violence,” Police Chief Randy Smith said in a written statement.

Wilson was asking people to leave the party at the request of the homeowner when he physically bumped into Harris, who was at the party with his cousins, Ward and Brandon. An argument broke out, and the trio left but returned a short time later with a gun.

Wilson and Harris began arguing again outside the house, police said, then Ward went into a nearby wooded area and shot at Harris, striking him several times. The three then fled.

“The victim never saw it coming. This was an ambush type of shooting. The victim and the suspects didn’t even know each other,” Smith said.

The three suspects were transferred Friday morning to the St. Tammany Parish Jail, where bail will be set.

Follow Sara Pagones on Twitter, @spagonesadvocat.