"Knock-knock" burglars strike Calif. communities

LA CAÑADA, Calif. -Detectives are warning residents in several Southern California communities -- including La Cañada -- about a string of home invasions being dubbed the "knock-knock burglaries," reports CBS Los Angeles.

Investigators say the break-ins are likely the work of several people, and law enforcement officials are urging residents to report suspicious activities, according to the station.

In one burglary, a suspect walked up to the front door and rang the doorbell -- making sure that no one was home -- and then went around the house, evading security cameras with an umbrella. His accomplices then entered the house through the front.

They then stole luggage, money and a safe and loaded everything into a BMW and drove away. Detectives have determined the group included three males and one female.

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

According to the homeowner, the suspects then 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 -- including jewelry, cologne and clothing.

Other communities have been affected as well, including Sierra Madre and Glenndale -- with burglaries occurring on a weekly basis.

Anyone with information about the burglaries is asked to call police.