Oceanside police are searching for the suspects who carried out a number of car break-ins near the city's northern beach.
Investigators released surveillance images of a man who may be involved, and they are asking for the public to help identify him.
The suspects have been targeting vehicles in a parking lot near the 1500 block of North Pacific Street. Most had valuables or personal items sitting in plain sight inside.
"Some people have witnessed their cars being trashed and nothing being taken," said Devan Halford, an owner of a nearby boat slip. "Some people have actually had their windows broken into."
He said visitors and mariners at the marina lots are targets because they leave their cars unattended for days at a time.
And with warm weekends bringing more people to the sea, the thieves have seen an opportunity.
Police have not said how many complaints they are investigating, but Jackie Arding, who works at the Nautical Bean in Oceanside, said she has heard of a dozen in the last month.
"From what I can tell it's been a few tourists that run in and people who have had their car out for a while," she said.
Police recommend that you remove all personal items from your car to prevent becoming a victim of a similar theft.
If you know anything about this series, call the Oceanside Police Department at 760-435-4911.