Simon Cowell is the latest swatting victim in L.A. -- someone called 911 Sunday and reported the "X Factor" judge was duct taped in his home and being held hostage.
Sources tell TMZ ... the female caller claimed Simon was bound and gagged in the bathroom of his Beverly Hills estate.
We're told cops responded in force but found nothing. Simon was at home at the time.
It's the latest in a string of swatting incidents. Other victims include Ashton Kutcher, Miley Cyrus and Justin Bieber.