Jonathan O'Shaughnessy, 24, was shot and killed Monday night in Richfield outside where he grew up, his sister said. (Vince Tuss/The Minnesota Star Tribune)

The young man killed Monday night in Richfield was shot as he headed home from a community dance "filled with friends, family and neighbors," his sister said Wednesday, pleading for the public to come forward with any clues in his death.

Jonathan M. O'Shaughnessy, 24, was "gunned down in the neighborhood he grew up in," said his sister, Kortney Nordrum. She spoke at an impromptu news conference near where the shooting took place, with family members at her side and a growing memorial nearby.

Police, who were called to the area of 64th Street and 4th Avenue S. at 11:21 p.m. Monday on reports that someone had been shot, have described the incident as a "drive-by-style shooting." Callers said that "four to five shots were fired and a victim was struck in the chest by gunfire," police said in a news release.

Officers found O'Shaughnessy lying in the street. Despite emergency measures by Richfield police and fire personnel and Hennepin County paramedics, he died at the scene.

Witnesses described the suspect vehicle as a gray 1990s minivan with a sliding door on the driver's side. The vehicle was occupied by four individuals, police said.

From 2012 to 2016, Richfield has had only three murders, according to the city's crime statistics.

"We don't believe he was targeted" or that he knew his assailants, Nordrum said of her brother, whom she described as athletic, kind, hardworking and fun-loving.

"He was just starting his life," she said. "Jonathan loved the city of Richfield. He grew up here."

Her brother attended Blessed Trinity Catholic School and graduated from the Academy of Holy Angels high school.

Nordrum pleaded for anyone with information to contact police. "Think about if this was your brother, your son, your friend," she said. "We need to know why he was killed."

Anyone with information is asked to call Richfield police at 612-861-9898 or Crime Stoppers of Minnesota, which is offering a $1,000 reward for information leading to an arrest and conviction, at 1-800-222-8477.

Karen Zamora • 612-673-4647

Twitter: @KarenAnelZamora

Kortney Nordrum, holding papers in her hand, was hugged Wednesday after reading a statement from her family about her brother, Jonathan O’Shaughnessy, near a memorial to him on E. 64th Street in Richfield. (The Minnesota Star Tribune)

Jonathan O'Shaughnessy (The Minnesota Star Tribune)