A wave of residential burglaries in San Mateo has prompted police to warn residents to keep an eye out for criminals pretending to be solicitors.

In October, more than 12 residential burglaries were reported in an area east of U.S. Highway 101 between Coyote Point and state Highway 92, police said.

The majority of the crimes were "door-knock" or solicitor burglaries in which suspects pose as service people or salespeople canvassing a neighborhood by knocking on doors, police said.

The suspects in many of those cases appear to be working in teams of two or more during weekday hours when most residents are at work.

If there is no response to a knock, the suspects typically check the perimeter of the home for unsecured doors or windows, or force entry through a door or window out of sight from the street.

The burglars have generally taken jewelry and electronic items, investigators said.

To help minimize the risk of daytime burglaries, residents should always lock doors and windows when leaving home, even if it's only for a short time, police said.

Added layers of security such as dogs, alarm systems, and Neighborhood Watch signs can be effective deterrents, according to police.

Police advise residents to prepare an inventory of valuable items at home by taking photographs of jewelry and engraving a personal identification number on electronic items.

Anyone who sees a crime in progress or anything that appears to be suspicious is urged to call 911.

Alert neighbors are responsible for the majority of arrests made in residential burglaries, police said.

Anyone who might have information about current investigations or ongoing crime trends is asked to call San Mateo Police Department investigations at (650) 522-7650.

Anonymous information can be given by calling the secret witness hotline at (650) 522-7676.