Tadas Kazakevicius Copyrigted/ Getty Images(HARRISONBURG, Va.) -- Police in Virginia said they believe an alleged serial killer whom they've dubbed the "shopping cart killer" may be responsible for the deaths of four people -- and possibly more. Authorities said Friday that a suspect who was previously charged with the murders of two women, whose bodies were found in a lot in Harrisonburg in November, is believed to be connected to the deaths of two more people whose remains were found this week in a wooded area of Alexandria. "We're here today to talk about a serial k...