SAN FRANCISCO (KTVU/AP) -- A 20-year-old man was shot to death while playing "Pokemon Go" at a tourist attraction along San Francisco's waterfront, authorities and a family friend said.
An unknown assailant shot Calvin Riley in the torso on Saturday night at Aquatic Park near Ghiradelli Square, the U.S. Park Police said. A family friend called it a random attack.
Riley was playing the hit mobile game with a friend when someone shot him from behind and took off, John Kirby, the family friend, told reporters.
"From what we know, there was no confrontation," Kirby said. "There was nothing said back and forth. It was just senseless, just came up and shot in the back and ran away for nothing."
Kirby said Riley and his friend had noticed someone watching them from the top of a hill that overlooks the park, but it was dark and they were mostly looking at their cell phones.
KTVU's Tara Moriarty spoke to some of Riley's former teammates Monday who say the Serra High School graduate was a rising star in the game of baseball and they can't believe he's gone.
"His work ethic was insane," said Kevin Welch, a former teammate. "His love for the game was ridiculous; he was always talking about baseball thinking about baseball."
"I played championship games with him, I went to battle with him, you know," said Billy Gatt.
More than half a dozen former teammates from Serra High in San Mateo, where Riley was a standout player, told us they were shocked when they heard the news that Riley was randomly shot and killed.
"How does that even make sense? Why would Calvin get shot? He's the nicest kid; like there's no way he could have provoked this," said Dominic Freschet.
"I know his buddy peeked around the corner and saw Calvin fall to his knees," descirbed Gatt. "And then he saw the shooter run. I think he only saw the shooter's back, though. His buddy went up to Calvin, I do know that, and Calvin did say his last words."
"He was the kind of guy that would give you the shirt off his back, the guy that was "team before me", the guy that was "you before me", you know?" said Gatt.
"Calvin was honestly a standup guy, real man, gentleman," said Welch.
National Park Service spokesman Lynn Cullivan said investigators believe there are witnesses to the attack because it happened in the bustling Fisherman's Wharf area. They are seeking tips.
There were no surveillance cameras in the area of the shooting, Cullivan said. "We would really love to have anybody who was down here who might have a cell phone video maybe taking a selfie putting something on Facebook, please contact the U.S. Park Police and let them know."
While the area is usually quiet at night, Cullivan said investigators are hoping that someone who was in the area might have seen or heard something relevant.
Sgt. Robert Jansing, a detective with the U.S. Park Police, said the gunman did not take any of Riley's belongings or try to rob him.
Riley graduated from high school in San Mateo and pitched for the baseball team at San Joaquin Delta College.
"It's a huge loss to everyone," the school's head coach, Reed Peters, said. "He was a great kid, a great competitor."
It's unclear whether the attack had anything to do with "Pokemon Go," which has become a national sensation this summer as legions of fans visit real-world landmarks in a hunt for digital creatures.
But the game's popularity has created unintended consequences in everyday life.
Property owners complain of players trespassing or damaging their grounds, and scores of players have been injured or robbed as they stare at their phones and try to track cartoon monsters.
Law enforcement officials have warned about the game's possible dangers, saying players can become engrossed in it and tune out their surroundings.
A Go Fund Me Page has been set up for Riley. Any possible witnesses who were in the area between 9 and 10 p.m. should call the U.S. Park Police tip line at (415) 561-5150, Cullivan said.