Janice Thibodeaux was taken into custody by authorities on a felony charge of battery after reportedly assaulting and attempting to choke Seymour following the taping of Cowell's hit TV show American Idol at L.A. Live.
According to TMZ.com, the 33-year-old suspect approached TV host Seymour and asked if she was Cowell's girlfriend before pouncing and attacking her.
Seymour, who remains close to Cowell after their split last year, is not thought to have suffered any serious injuries and refused medical treatment after the incident.
Thibodeaux is being held on $52,700 bail.
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