An upset El Cajon teen has a warning for all kids who ride bikes -- take precautions if you leave it at a bike rack.
"It's just really, really sad," said 14-year-old David Acevedo.
On New Year's Day, Acevedo and some friends rode their bikes to a Target store in Rancho San Diego.
With the key to a bike lock left at home, one of Acevedo's friend guarded the bikes as the teens shopped, but eventually the friend had to leave to go to a class.
About five minutes later, Acevedo and his other friends returned to the bike rack, and the teen discovered his $450 bike was gone.
"My heart was racing and I was just kind of in shock," said Acevedo.
He spotted a deputy who tracked down some surveillance video from Target.
In the video, a car -- possibly a Volkswagen Beetle -- pulls up near the entrance. A man is seen getting out before a woman gets out of the passenger side and gets into the driver's seat. She pulls into a parking spot, and soon after, a man is seen taking off on Acevedo's bike as the Volkswagen pulls away.
For Acevedo, there was a sense of disbelief.
"I was not expecting it at all in a busy place like this," said Acevedo.
Mired in the disbelief was another feeling.
"I have a lot of regret," said Acevedo.
That regret sparked this warning for other kids: "Always use a lock, because there's always going to be somebody looking for something to take," said Acevedo.
One security expert 10News spoke to said the thieves were likely patrolling the parking lot looking for victims.
The Acevedo family shared the surveillance video on social media, including the East County Emergency Update Facebook page, to warn others.
If you have any info on this case, you are urged to contact the Rancho San Diego sheriff's station.