Thieves are targeting the cars of women while they're in the gym, both in Wyckoff and Ridgewood.
It's a text book crime of opportunity.
Thieves in Bergen County smash car windows and grab the goods inside; valuables too enticing for these crooks to leave behind.
Police say it's happened a half a dozen times in the last couple of months at gyms in Ridgewood and Wyckoff.
"Do you leave things in the car?" Eyewitness News asked.
"Yes. I guess my GPS. I don't leave anything else though. I'll put it away from now on," said Breen Meyer, a driver. "I'll be more cautious now. I wasn't aware of it."
The Wyckoff YMCA parking lot has been hit twice and the Ridgewood New York Sports Club has seen it too.
The incidents have all happened during the day while the victims were inside working out.
Cara Polizzi doesn't take any chances, but understands why some people aren't always so careful.
"I know some moms tend to because you're in a rush, but I always take it. It's easy with the stroller," Polizzi said.
So police are warning everyone: lock valuables in the trunks or take them with you.
"I'm careful, I don't leave things in my car that I shouldn't," said Jeff Clutterbuck, a driver.