Think again before going to sleep with a window or door unlocked.

A string of cat burglaries in Surprise is serving as a wake-up call for residents who wouldn't dream someone would steal their property as they were asleep.

The pattern, police said, is burglars are entering through unlocked sliding glass doors, back windows or doors.

The latest cat burglary was Tuesday morning in the 14400 block of Shaw Butte Drive, in the Copper Canyon subdivision. This was the third one in the community and sixth overall in the past week.

Tuesday, a resident awoke at 4:30 a.m. to find a suspect in her bedroom. The burglar fled after stealing cash and credit cards. Police said the suspect entered the home through an unlocked rear door.

Other burglaries have occurred while residents were home. The suspects entered through non-secure doors, windows and dog doors and cash and credit cards were stolen.

Sgt. Mark Ortega said burglaries when residents are home are not common and it has been about eight years since there was a string of cat burglaries. But chances increase when cool evenings tempt residents to leave windows and doors open or unlocked.

"(Cat burglaries) go in cycles," Ortega said. "We see one and then don't see one for a long time. It's uncommon to see someone get the nerve or predisposition as brazen as that, though. All it takes is an open invitation."

Ortega said police have investigated other homes where the screens were removed from windows and the burglar found the window locked.

"To the common cat burglar, the objective is to get in as quickly and easily as possible."

Burglaries through dog doors are fairly common during the day, Ortega said. The dogs apparently haven't been alerting residents of the intruders.

"It's hard to say what this person's experience is or knowledge of dogs is, or if they know how to handle them and can get away," Ortega said.

Ortega said police are increasing patrols in the area, and are processing evidence collected at the crime scene.

Meanwhile, residents need to be diligent in protecting themselves.

"Honestly, this all falls right back to the residents, and it's up to them to lock doors and windows," Ortega said. "I wish we had an officer for every house to lock up for them, but we can't."