Authorities say they were able to use footage from a blue light camera to identify the vehicle associated with the incident.
The suspect was taken into custody, but their identity has not been released.
The Merced Police Department responded to the park at 25th and P streets at 3 p.m. on Wednesday for reports of gunshots.
Lt. Jose Barajas says officers found a man in his early 20s suffering from multiple gunshot wounds.
The man was taken to the hospital but died from his injuries.
Barajas says the shooting was isolated but happened in a public place where bystanders could have been hurt.
This was the 5th homicide of the year in Merced.