High-powered guns purchased at Houston-area stores by a Gulf Cartel cell and smuggled across the border for the syndicate's bloody warfare have been traced to at least 55 killings in Mexico, including the deaths of police officers, civilians and gangsters, federal agents said Thursday. The recent tracking of firearms is the result of a four-month anti-cartel operation focused largely on Houston, which the federal government contends is the No. 1 spot in the United... (GunPolicy.org)