Armed thieves tied up a guard at a Los Angeles warehouse and stole more than 7,000 laptop computers worth millions of dollars, according to police. Los Angeles police said the heist started when a gunman confronted a security guard posted at the gate of a warehouse near 190th Street and Western Avenue in the Harbor Gateway area late Friday evening."Zip tied the security guard and then gained access to the parking lot of the business. At that time, approximately four other suspects assisted with driving in two trucks to attach two trailers and they drove away with two trailers," Capt. Gary Walters with the Los Angeles police said.