In this Dec. 11, 1998 photo, rescue workers remove the body of a victim of a gas explosion that killed four and leveled six buildings in downtown St. Cloud, Minn. An Associated Press investigation has... more 
In this Dec. 11, 1998 photo, rescue workers remove the body of a victim of a gas explosion that killed four and leveled six buildings in downtown St. Cloud, Minn. An Associated Press investigation has found since 1968, there have been at least 270 natural gas accidents in the U.S. that could have been prevented or made less dangerous by an inexpensive valve that cuts off leaking gas. At least 67 people have been killed and more than 350 hurt. Yet nearly 90 percent of the nation's gas service lines aren't fitted with the valves. (AP Photo/The Minneapolis Star Tribune, Cheryl Diaz Meyer) less 
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Associated Press | Photo By The Minneapolis Star Tribune, Cheryl Diaz Meyer
Mon, Jul 23, 2012 4:43 PM EDT