UPDATED: This video from On The Red Carpet shows Paris identifying the assailant: "Oh my god! That's another intruder who came to my house on a bike... he attacked my security at my home."
As Hilton's bodyguard escorts the man toward the courthouse, the assailant says his name is Jim Rainford and that he has obtained the consent of HIlton's father to marry her.
Someone asked, "So you already proposed to her and she said yes?" The assailant affirms, "Yes she did. I've got the picture in my pocket, and I'll show you." Then later he clarified: "I wanted her to autograph my picture of me proposing to her.
PREVIOUSLY: LOS ANGELES (AP) -- A man tried to grab or hit Paris Hilton's boyfriend as the couple headed into a Los Angeles courthouse where the socialite was to testify against a man accused of an attempted break-in at her home.
The incident Wednesday outside the Superior Court building in Van Nuys was witnessed by an Associated Press photographer and reporters who were interviewing the couple.
All photos by AP Photo/Nick Ut. Story continues below.
The man appeared to get a hand on the neck of Hilton's boyfriend Cy Waits but was immediately seized by a bodyguard and taken away.
Hilton has posted on her Twitter account that a "psycho intruder just punched Cy in the back of the head as we were walking into the court house."
Police Officer Cleon Joseph says the man has been detained and an investigation is under way.