Bronxville police are doubling overnight patrols and warning residents to lock their doors after a series of break-ins in the upscale neighborhood.

The village has suffered three break-ins in less than two weeks, and police have made no arrests.

Investigators say at least two of the crimes are connected. Darkly clothed burglars forced their way through second-floor windows and took off with cash and jewels. They reportedly hit one homeowner in the head with a flashlight when he got in their way.

Typically, burglars will flee if they are spotted, says village police chief Christopher Satriale. When they attack a homeowner and continue to burglarize the home, it's cause for extra concern, he says.

Police are advising residents to lock their doors and windows. They are also asking for anyone with surveillance video near the three previous burglaries to share it with investigators.

Police say they are checking pawn shops for stolen items.