(IDEX Online) - Police are hunting three robbers, believed to be armed, who used sledgehammers to smash display cases at a jewelry store in Charlotte, North Carolina, USA.They entered Fink's Jewelers, in Birkdale Village, at lunchtime last Tuesday (11 July) wearing hooded sweatshirts and full-face mask and ordered staff to one part of the store while they stole jewelry. Nobody was hurt in the raid.The Jewelers' Security Alliance highlights this and other crimes in its latest update.In Gulfport, Mississippi, a man with a handgun demanded a showcase of lab grown diamonds.And in Memphis, Tennessee, four suspects broke in through the front window of a watch and jewelry repair business with sledgehammers and crowbars.All three crimes took place on the same day, 11 July.Pic shows suspects in raid on store in Charlotte, North Carolina.