Robbers in San Francisco are targeting victims with high-end watches worth thousands of dollars, authorities said.
Since June, the San Francisco Police Department has been notified of at least 20 armed robberies involving wrist-wear.
"This is an organized group of suspects who are getting together. They are specifically targeting people, and we do believe there is some level of surveillance or following beforehand," police Sgt. Adam Lobsinger told Fox San Francisco.
Investigators believe the robberies are organized and coordinated by multiple suspects. Many of the incidents have occurred in busy areas and destination spots within the city, police said.
Some victims have fought back and sustained injuries in the process, police said.
"Fortunately, we have not seen major injuries. But one thing that we always remind people, if you are the victim of this type of crime, to not fight back," Lobsinger said. "At the end of the day, this is a property crime, your watch can be replaced, but you can not."
San Francisco has dealt with a series of brazen robberies and retails going back to last year. The thievery got so bad, some corporate chains like Walgreens decided to shutter several locations in the city.
Investigators are reviewing security videos that captured some of the robberies, police said.
Meanwhile, authorities are warning people to keep their valuables out of sight and walk and travel with others so they can to avoid becoming a victim.