$110,000 reward in killing of ‘Pokémon Go’ player Calvin Riley

Calvin Riley was shot to death in San Francisco last August. No arrests have been made in his killing. Calvin Riley was shot to death in San Francisco last August. No arrests have been made in his killing. Photo: Riley Family Photo Photo: Riley Family Photo Image 1 of / 4 Caption Close $110,000 reward in killing of ‘Pokémon Go’ player Calvin Riley 1 / 4 Back to Gallery

Nearly a year after a college sophomore was mysteriously slain while playing “Pokémon Go” at Aquatic Park in San Francisco, authorities and the victim’s family are offering a $110,000 reward for information leading to the killer’s capture, U.S. Rep. Jackie Speier announced Monday.

“It has ripped the family apart,” said Speier, D-Hillsborough. “I think all of us who have young adult children who make their way around the city doing innocent activities — just doing normal, everyday activities — should not be in fear of being gunned down by a person and then have the crime go unsolved. It’s just wrong.”

Calvin Riley, a 20-year-old graduate of Serra High in San Mateo, was a pitcher for the Delta College Mustangs in Stockton when he was shot in the chest while playing “Pokémon Go” on Aug. 6. Paramedics tried to revive Riley, but he died at the scene.

At a news conference Monday near the spot where Riley fell, Speier and the victim’s mother, Kariann Riley, announced a $50,000 reward offered by the city of San Francisco to match the reward the family has been offering since February. U.S. Park Police, who are investigating the homicide, will also offer $10,000, officials said, bringing the total to $110,000.

“It’s been hell. We’re living a nightmare every day,” Kariann Riley said. “We still feel like he’s coming home.”

“We will not allow it to become a cold case,” Speier said.

Detectives are seeking two vehicles possibly connected to the shooting — a dark 2006 to 2009 Audi A3 Wagon and a white 2013 four-door Hyundai Sonata — but are still searching for a motive.

Investigators “have interviewed numerous friends and associates of Calvin, and at this time we haven’t found someone with a motive to harm him,” said Jerry Marshall, a U.S. Park Police spokesman.

Filipa Ioannou is a San Francisco Chronicle staff writer. Email: fioannou@sfchronicle.com Twitter: @obioannoukenobi