A search of the Mark Twain Bridge Thursday night blocked traffic for a time on I-72.
Marion County Sheriff Jimmy Shinn says an anonymous caller to Marion County 9-1-1 warned of a possible bomb or explosives on the bridge. No device was located during the resulting search. The bridge was closed around 9 a-m. Hannibal Police are working to identify the caller. Sheriff Shinn says the call originated from a business on Market Street. The investigation is ongoing.