Investigators say two men, described as Asian males in their 20s, are asking residents if they can step inside their homes to use a phone or bathroom. Once they're let in, they draw their guns or assault the victims before taking their jewelry.
Police spokesman Peter Panos said homeowners should use extra caution if approached by strangers at the door.
"Helping someone out, especially in wintertime, is very admirable," Panos said. "They come up, 'My car's broke down, Can you let me in to use my phone? Can I come in to stay warm until somebody comes?' The biggest thing here is, if they need someone to come assist them, and they need to stay warm, and you don't know these people, call us. We'll be glad to give them a place to sit in our car or find them a place to stay until their ride comes."
Investigators know of four such cases in the past several weeks. Panos said any additional victims should report the incidents to police. He said if the suspects are caught, police will be able to identify the jewelry and return it to their owners.
Police say residents should use extra caution when approached by strangers at their door. Officers are urging families to call police if they wish to help someone in distress rather than letting them into their homes.