Officials say safety concerns prompted additional security measures on a Southwest plane that landed in Nashville on Sunday. Flight 3596 originated in Kansas City. The flight stopped in Nashville for a connection around 2:15. Southwest spokesman Chris Mainz tells the Tennessean that passengers on the flight were re-screened out of an abundance of caution, but he didn’t elaborate on exactly why the additional measures were taken. On Saturday, a Southwest plane bound for Albuquerque diverted to Nashville after the flight crew said a male passenger was acting suspiciously. The passenger was detained and questioned by authorities and later cleared to continue on the flight.