SAN DIEGO — A man was shot on a street near an Otay Mesa park and middle school early Sunday morning, police said.

A caller told police their friend had just been shot around 12:30 a.m., according to a San Diego police news release. Officers headed to Arey Drive, near Montgomery Middle School and the Silver Wing Recreation Center, where they found a 23-year-old man suffering from multiple gunshot wounds.

Paramedics rushed him to the hospital, where he was treated for “serious injuries,” police said.

Detectives were still looking into the basic circumstances surrounding the man’s shooting Sunday morning.

The Otay Mesa shooting was one of four that happened over the course of a few hours in San Diego late Saturday and early the next morning.

In Pacific Beach, friends rushed three victims to the hospital after they were shot in an alleyway near Crown Point Park. Outside the Bahia Resort Hotel in Mission Beach, someone in an SUV shot a man standing in the parking lot. And in City Heights, a man showed up at a gas station off Orange Avenue and 43rd Street with multiple gunshot wounds.

Police did not have detailed descriptions of the shooters or much information about what led up to each attack as of Sunday morning.