(CREVE COEUR, Mo., AP) — An Adopt-A-Highway sign is expected to go up by Jan. 1 in St. Louis County for a group that has questions about the government’s official version of the Sept. 11, 2001, terrorist attacks.

KMOX Radio (http://cbsloc.al/RmS9eZ) reports that the “St. Louis 9-11 Questions Meet Up Group” has agreed to keep clean a stretch of Olive Boulevard between Lindbergh and Old Bonhomme in Creve Coeur. Group organizer Donald Stahl believes the World Trade Center towers in New York may have been brought down by a controlled demolition.

His group also believes United Flight 93 crashed in Pennsylvania into a hole that was already there, and members suspect it was a missile, not a plane, that hit the Pentagon.