Exclusive: Sources Say Richie Collapses at Hyde

Sources tell TMZ that Nicole Richie passed out at Hyde nightclub early Sunday morning in Hollywood.

We're told it occurred just before 2 a.m., when Richie passed out and fell to the floor. An employee approached Richie and her friends and said he was calling 911. Sources say they told the employee not to make the call and that they would take Richie to a hospital. The friends then carried Richie out of the club through the back door. TMZ does not know if Richie went to the hospital.

Before Richie collapsed, we're told she hung out for awhile with Lindsay Lohan inside the club. Lohan had her own bizarre tale early Sunday morning on a street in Hollywood.

Late last week, Richie's reps confirmed that the "Simple Life" star entered a treatment facility to determine why she hasn't gained weight. Richie has looked shockingly thin over the last few months.