CHICAGO (AFP) - The toll from the deadliest single tornado to strike the United States in more than six decades has risen to 138, officials said Thursday. The toll rose after four critically injured victims died in hospital, the Missouri Department of Public Safety said in a statement. The mile-wide May 22 twister reduced a third of the Missouri town of Joplin to rubble, tearing apart homes, businesses, a hospital, churches and schools along a four-mile (six-kilometer) path of destruction. With phone service knocked out and families scattered in search of a safe place to sleep, the state patrol was called in to help sort through thousands of request for help finding missing loved ones.