The Jewelers’ Security Alliance is warning retailers in the Sacramento, Calif., area that there have been an “unusually large number” of three-minute burglaries during the past few months. The areas that have been hit hard include Rocklin, Citrus Heights, Lincoln, Elk Grove, and Woodland, JSA said in its “Crime Alert” electronic newsletter.

A three-minute robbery is when one or more persons break into a closed store by force and take as many items as they can, getting out within three minutes. The robberies are always at night and rarely have any witnesses. Burglars know that an alarm will sound, but they plan to be out of the store in less than three minutes, before there can be any alarm response.

JSA said in its newsletter that jewelry merchandise left out of the safe overnight is always at risk, especially when the jewelry can be seen from the street. “It’s a very common crime,” John J. Kennedy, JSA president, told JCK. “But after a while we started seeing an unusual concentration [in the Sacramento area] and it was continuing in a wave, sometimes three a day, and more than that. It became a pattern.”