Photo Credit: WireImage

After picking out matching his-and-hers vintage Carrera sunglasses at a Grammy gift lounge on Feb. 6, Rihanna and her boyfriend, Chris Brown, headed over to Timbaland's pre-Grammy bash at Boulevard 3 in LA. "It's going to be cool," Chris told Life & Style when asked about Rihanna's performance that night.

But Chris didn't seem to be having much fun as the party carried on. "I saw him and Rihanna fighting," an eyewitness tells Life & Style exclusively. "They were in this room, and they were just screaming at each other, totally cussing each other out. They were screaming, 'F--- you,' 'No, f--- you' at each other, back and forth."

For more on Chris and Rihanna's explosive fighting, pick up the latest issue of Life & Style, on newsstands now!