LA CAÑADA (CBSLA.com) — Detectives are warning residents that so-called “knock-knock burglaries” have been occurring on a weekly basis in several communities, including La Cañada.

One of these groups of burglars was caught on camera, breaking into a home May 8. In the video, one burglar walks up to the front door and rings the doorbell.

READ MORE: Authorities Arrest Suspect Involved In Pursuit Of Suspected Stolen Vehicle, Possible DUI

Upon realizing that nobody is home, he is seen going around the side of the house, evading cameras with an umbrella. His accomplices then enter through the front door.

Detectives determined that the group includes three males and one female, who stole luggage, money and a safe. The burglars loaded everything into a BMW and drove away.

In another incident, a group of burglars infiltrated a home after breaking down a back door about 9 a.m. on a weekday.

READ MORE: Californians Could Soon Be Fined For Using Too Much Water

The victim of that burglary says the suspects ransacked his home, and made off with credit cards and two laptops. Investigators say those four suspects bought $2,000 worth of merchandise at a Macy’s in Northridge, including jewelry, cologne and clothing.

Sheriff’s deputies say they are increasing patrols and urging residents to report suspicious activity.

“The burglars that we have caught in action was because a neighbor looks out and sees that something is not right,” Sheriff’s Department detective Rodger Burt said.

Investigators say the break-ins are likely the work of several different groups.

MORE NEWS: USC Student Second of Three Confirmed Omicron Cases In LA County

Anyone with information on these crimes is urged to contact police.