DETROIT -- Gangs from South Americaare breaking into multi-million-dollarhomes across the country, includingmetro DetroitPolice said they are highly functionaland well-trained.A police official described the crews.which are believed to consist of fourto six people, as highly functional andwell-trained.The thieves reportedly use a jammerto overcome wireless security systemsthat depend on WiFi to operate. Thecrews are all dressed in black, withbackpacks, and gloves. They arenon-confrontational, and their goal isto get in and out of the homes quickly,police said.