Tornadoes roll through Dallas area

Several reported tornadoes tore through the Dallas area on Tuesday, tossing semis in the air and leaving crumpled tractor trailers strewn along highways and in truck stop parking lots. The National Weather Service reported at least two separate "large and extremely dangerous" tornadoes south of Dallas and Fort Worth. Dallas Police spokeswoman Sherri Jeffrey said an apparent twister touched down and caused damage within the city’s southern limits.