One man was arrested in connection to the July mass shooting near a Brooklyn playground that left one dead and 11 others injured, the NYPD confirmed Wednesday night.

20-year-old Brooklyn resident Kyle Williams faces multiple charges, including second-degree murder, attempted murder, and criminal possession of a weapon.

In one of the more disturbing shootings in New York City in recent memory, shots erupted just as the crowd at the annual Old Timers' Day block party at the Brownsville Playground was beginning to disperse July 27.

A 38-year-old man died after he was shot in the head, a New York City police spokesman said. The 11 other victims ranged in age from 21 to 55 years old.

Police did not confirm Wednesday night if they were looking for additional suspects, but the NYPD said in early August that the shooting was between two groups and stemmed from a previous dispute. Two firearms were recovered at the scene, and 15 shots were fired between the groups, according to investigators.

Police Commissioner James O'Neill said 2,000 to 3,000 people attended the event next to the playground, and that more than 100 police officers were stationed there.

"One of the worst experiences of my life," Brooklyn Democratic Councilwoman Alicka Ampry-Samuel tweeted. "How does such a beautiful and peaceful event become overshadowed by tragedy in seconds?"

"It was chaos," Gary Miller, a 60-year-old vendor at the event, told the New York Post. "Shots rang out and the crowd was already dispersing and you heard about 9 to 11 shots and everyone was running and scattering for cover."

Brownsville is an east Brooklyn neighborhood that has continued to struggle with gun violence, even as New York City streets become safer than they have been in decades.