KTLA

Suspect arrested in fatal party shooting of Rancho Cucamonga teen

A teen suspect was arrested Tuesday in connection to the murder of a 15-year-old old boy from Rancho Cucamonga.

The suspect was identified as Israel Diaz, 19, from Bloomington, by the San Bernardino County Sheriff’s Department.


Diaz is accused of murdering 15-year-old Robert Plyley on Nov. 1, 2022.

The Alta Loma High School student was shot and killed at a Halloween party in the 10600 block of Geronimo Avenue in Bloomington, authorities said.

An investigation revealed that a large gathering was held at the location and a fight broke out outside. Authorities said video evidence showed Plyley stepped in to stop a male from fighting a female and was struck by gunfire.

Officers responding to the scene found Plyley lying on a driveway with a gunshot wound. He was taken to a hospital where he later died.

The suspect, Diaz, fled the scene and investigators believed he was likely in Mexico.
Detectives began working with the U.S. Marshalls Service and the Department of Homeland Security to locate Diaz and extradite him back to the U.S.

On April 25, Diaz was arrested by the U. S. Border Patrol as he attempted to enter the U.S., authorities said.

Diaz was booked at the San Diego County Jail and “will be transferred to the custody of the San Bernardino County Sheriff’s Department in the coming days,” officials confirmed. He is being held without bail.

The victim’s family described the teen as ambitious, athletic and energetic.

“He loved to laugh and have fun, his energy was like no other,” said his mother, Christina Mensen. “I miss my son. I miss his smile and his hugs. I miss his voice, his laugh.”

In a statement to KTLA, the Plyley family thanked the community for their love and affection during this “tragic time,” and encouraged people to hold their loved ones close.

“We are all at a lost missing the HUGE sunburst of energy that is Robert,” the family said.

Anyone with information about this case or who may have video from the party is asked to contact Detective David Carpenter at 909-890-4904 or email PAffairs@sbcsd.org.

Anonymous tips can be submitted to We-Tip at 800-78CRIME or at wetip.com.