An investigator talks with police officers at the scene of a multiple fatal shooting in front of the City Grill bar and restaurant in Buffalo, N.Y., on Saturday. (David Duprey/Associated Press)

The chief prosecutor in Buffalo, N.Y., got a judge to dismiss murder charges against a man who had been accused of opening fire outside a downtown Buffalo restaurant, killing four people and wounding four others.

Erie County district attorney Frank Sedita says photo evidence and witness statements do not back up the charges against 25-year-old Keith Johnson of Buffalo.

Johnson had been charged with four counts of second-degree murder in the shootings outside City Grill early Saturday. The charges were dismissed Sunday morning.

Johnson is still being held on a parole violation and could be rearrested if authorities change their minds.

Daniel Derenda, the police commissioner, said there was plenty of evidence to charge Johnson, including witnesses who identified Johnson by name.

Shootings followed altercation

Managers had decided to close the City Grill in the city's business district after an altercation inside. The victims were leaving at about 2:30 a.m. ET when a man who had been inside began shooting, police said.

"There were verbal things going on," said Dennis Richards, the chief of detectives. "Management apparently chose to close down and have everybody leave the restaurant. People were leaving when this shooting happened."

A group was attending a party in advance of a more formal anniversary celebration scheduled for later Saturday, authorities said. The couple, Danyell Mackin, 30, and his wife, Tanisha, married in Texas a year ago and had returned to celebrate with Buffalo-area friends and family, authorities said.

Danyell Mackin was killed. His wife was not hurt.

Police identified the other three victims as Willie McCaa III, 26, Shawnita McNeil, 27, and Tiffany Wilhite, 32.