Photo: Union City Police Department

Authorities are searching for suspects in the fatal shooting of two boys at an elementary school parking lot in Union City early Saturday.

Police are withholding the victims’ names because they are minors, but Lt. Steve Mendez, a Union City police spokesman, said the boys were ages 11 and 14.

Mendez said the boys were sitting in a van in the west parking lot and were “confronted by unknown suspect(s) who shot into their vehicle multiple times.”

As of Sunday morning, investigators have not made any arrests or identified any suspects in the shooting, Mendez said.

Officers responded to 911 callers who reported hearing gunshots in the area of Sherman Drive and Colgate Drive at 1:26 a.m. Saturday, according to the Union City Police Department.

Officers found the victims with gunshot wounds in the parking lot of Searles Elementary School, 33629 15th St.

The 14-year-old boy died at the scene. The 11-year-old victim died on the way to the hospital, police said.

“The Union City Police Department is diligently looking into the motive for this tragic incident,” police said.

The Alameda County Coroner’s Bureau on Sunday said police placed a hold on releasing the victims’ names.

John Thompson, the New Haven Unified School District superintendent, said in a statement Saturday that one of the boys is a student in the school district, and the other a former student.

“We will have support for our students and staff at the sites where these students attended when school resumes after the Thanksgiving break,” Thompson said.

Crime scene investigators recovered shell casings among other unspecified “items of evidence” at the scene, police said. Union City police posted a photo of the scene to its Facebook page, showing multiple yellow crime scene markers dotting the parking lot.

It’s the second double shooting in the quiet East Bay city in a week. The first happened early Wednesday, when two men in their 40s were shot in a parked car at Eighth and C streets. Another vehicle pulled up beside them, and someone inside opened fire, police said. Both victims survived.

Police are investigating whether the two shootings — which happened roughly seven or eight blocks apart — are connected, Mendez said.

“We haven’t ... ruled (it) out,” he said.

Lauren Hernández and Rachel Swan are San Francisco Chronicle staff writers. Email: lauren.hernandez@sfchronicle.com, rswan@sfchronicle.com Twitter: @LaurenPorFavor, @RachelSwan