(CNN) -- An active-duty service member found a note Thursday afternoon at Joint Base Charleston in South Carolina that said "I have a hostage," triggering a two-hour shutdown of the base.
Within a short time after the note was discovered, security officers had locked down the entire base by 5 p.m., according to Rose Alexander, a base spokeswoman.
The office building on base where the note was found was evacuated and searched, and nothing out of the ordinary was found. Then the entire base was locked down and security ran a routine check to make sure all personnel were accounted for.
By 7 p.m., the all-clear was given and the gates were opened.
Joint Base Charleston, home to thousands of military and civilian workers, was created by the merger of Charleston Air Force Base and Naval Weapons Station Charleston. It is home to a unit of large Air Force cargo planes that are used on missions around the world. The base is still under Air Force command.
As for the note which was written on "sticky paper," it is still under investigation, Alexander said.