SPOKANE, Wash. -

As local residents try to beat the heat at riverside beaches, car prowlers are showing up at trail head parking lots to steal the stuff you don't take with you to the river's edge.

Car prowling at trail heads has happened approximately 75 times so far this summer and the problem has gotten so bad at Boulder Beach and Plante's Ferry Park that Spokane County Sheriff's deputies have been leaving behind pamphlets on windshields warning drivers they're in a car prowling hot spot.

Thieves know if you're heading for the water, you're leaving behind the stuff you don't want to get wet in your car. It's been a sizzling summer and so after work, a lot of us are heading to the water to cool off.

“We go out here to go swimming, cool off, play in the sand and have fun,” Boulder Beach regular Debbie Croston said. She knows the busy parking lot at the beach can give thieves a lot of targets to choose from, especially when swimmers try to keep their electronics and wallets from getting wet by stashing them in the car.

“People take things out of their pockets because they don't want to get them wet, leave them in their cars and it's an opportunity for some of the criminals to go and cause those people to have a bad day and be a victim,” Spokane County Sheriff's Deputy Mark Gregory said.

“Lock up you cars, don't leave anything that's visible, no phones, no iPods nothing. make it look like there's nothing in your vehicle or just take it with us,” Croston said.

The sheriff's office is now using some of its undercover deputies to catch thieves stealing from cars, but you should plan ahead and leave as much as you can at home.

“We are trying to hit the areas that are being targeted by these thieves and we are trying to get this information out through the media and other sources, trying to get people to watch out for themselves or they can be a victim of these crimes,” Gregory said.

Right now because of staffing shortages the sheriff's office is not running bike patrols that in previous summers protected beaches along the Centennial Trail, that's why if you witness or are the victim a car prowling you need to report it so deputies can better focus their resources on the problem.