According to the New York Post and several photo agencies, while Paris and boyfriend Doug Reinhardt seemed cheerful early in the evening at Heidi Klum's 10th Anniversary Halloween party, later in the evening, they were feuding.
At one point, as evidenced in this photo, Doug reached around from the back seat of their limo and was restraining Paris.
Photographer Ramon Alves told the Post, "She was mad… She jumped in the front seat and [Doug] was holding her around the neck saying, 'Relax, relax.' "
The couple headed from Heidi's party to the Roosevelt Hotel and then reportedly left there at around 3:30 AM.
And then, things really got strange.
At the corner of Sunset and La Brea Boulevard, their limo then reportedly came to a stop as Paris' cell phone went flying through the vehicle's window.
Witnesses on the scene reported Paris looking for the phone and not finding it, and ranting at Doug for throwing it out of the window.
A witness told the Post, "It got very physical. The limo driver was horrified!"
But on Sunday morning, all seemed to be A-OK in the heiress' world. On her Twitter account at 5:14 AM on Sunday, November 1, she wrote, "Tonight was amazing! Had the best Halloween ever! loves it!"
She later Tweeted, "Had such a relaxing day with my love. Doug and I barbequed and have been watching football all day. I love Sundays!" and "I had the best Halloween ever! What did everyone do on Halloween?"
Related Content from AccessHollywood.com:
PLAY IT NOW: Heidi Klum's 10th Annual Halloween Party (October 31, 2009)
PLAY IT NOW: Halloween Morning Mayhem 2009!