CHICAGO (CBS) — Call them the rehab robbers.

Police say thieves on the South Side are targeting workmen on the jobs as they are renovating homes and apartment buildings. As CBS 2’s Roseanne Tellez reports, police are warning contractors and homeowners, to be on alert.

“We don’t keep much money on us,” one worker said Monday.

But other properties being rehabbed were not so secure.  There were open gates and unlocked doors.

Armed thieves have taken advantage. Chicago police say there has been a string of armed robberies at rehab sites in the Chicago Lawn and Marquette Park neighborhoods.

There are plenty of boarded up buildings there — some being worked on, others abandoned. Residents say any vacant property in the neighborhoods is boarded up to keep thieves from breaking the windows.

That’s what Yajaida Rodriguez did after purchasing one property.

But before she could move in, the place was ransacked. Thieves took the bathroom tub and sink and ripped into the wall for the pipes.

“They took all my counter tops. They ripped the up the wall, they took the piping,” she said.

And yes, they got the kitchen sink.

The thieves are “disregarding other people’s property basically,” Rodriguez said. “So now I have to start again.”

With regard to the workers, Area One detectives are warning construction crews to lock the doors and gates. Don’t leave property in plain view.