While the evening started out in a pleasant fashion, everything went downhill for Paris Hilton and Doug Reinhardt after leaving Heidi Klum's Halloween party at Voyeur nightclub on Saturday night (October 31).
According to a paparazzo source, the couple then headed to another party at Roosevelt hotel in Hollywood, where they stayed for a few hours.
As the on-again/off-again pair headed back home, photographers following them saw a cell phone flying out the window on the corner of La Brea and Sunset, during which time the limo stopped and Paris jumped out of the car to find her mobile.
Our insider adds that the hotel heiress "went back to the limo with her hands empty - yelling to Doug that she wanted to kill him for throwing her cell out of the car."
As the limo started moving again and stopped a few blocks away, photographers approached the car to find Paris slapping Doug on the back seat, with Doug finally immobilizing his lady by holding her down before friends quickly tried to block the paparazzi from witnessing the troubling domestic moment.
Enjoy the pictures of Paris Hilton and Doug Reinhardt out on Halloween (October 31).