When you think of bike thief it's usually a guy with pliers and other tools lurking around

in a Hoodie or something. Now some of these bandits are getting bold with rocks and cars.

On New Year's Eve Andrew Christman says thieves used three rocks to break into the side door at his Pedal of Littleton shop. They stole four bikes worth $30,000.

"They definitely smashed and grabbed the good stuff," he said. "You kind of get that lost empty feeling."

And he's not the only one.

"You get an alarm the goes off and it just says glass broken or something along those lines and when I got here it's like there's no front of the store left," Adam Williams said. "They basically backed up a pickup truck through and took out the front of the store over there."

His SloHi Coffee + Bike shop was hit in November. Jinji Cycles up the street from SloHi robbed twice this summer.

"They broke the windows came in and grabbed some bikes and we're gone within 30 seconds," Kyle Lofstedt, Jinji manager said. "Thieves will be thieves. It's just a mindset and it's just really sad. It's a really sad thing."

But the most recent in these smash and grabs happened at C3 or Colorado Cycling Connection last month. The owner tells us a van reversed through the storefront and stole four bikes.

"It seems to me like it's happening more frequently," Williams said.

"Who's next, ya know?" Christman asked. "Like who's the target. You know they're coming and then when is it going to happen?" -

So what can these shops do besides fill out a police report? They say beef up security.

"Refreshing all the locks outside, thicker cables, adding additional security lights outside and hopefully doing some security film so that if they broke it they couldn't actually get through it," Christman said.

"After the first one we cabled all of our bikes together," Lofstedt said. "They tried to take one out of the window but it ended up just not going."

We have reached out to Denver Police and the Littleton Police Department. They say these cases are still open and active but Denver Police wouldn't say yet if they're connected.

"They say there's a special place in hell for bike thieves," Christman said.