Britney Spears' Appearance at the 'I Am Still Music' After-Party Causes 'Pandemonium'

Nicki Minaj and Britney Spears are scheduled to go on the road together this summer and according to analysts, this tour could very well be a huge success, if Spears' appearance at the Factory in West Hollywood for Minaj's after-party is any indication.

According to E! Online's reports, fans were thrilled to see Minaj at her "I Am Still Music" after-party. However, they were even more ecstatic to witness the surprise appearance of Britney Spears. Some sources even said that Spears caused complete "pandemonium."

"[It] was complete pandemonium. Six people were carried out after hyperventilating. They literally fainted when Britney walked onto the stage where Nicki was hanging, " said the E! Online's unnamed source. "People were crowd surfing to get to the stage. " This source also stated that fans screamed so loud for Britney and Nicki that their voices drowned out the music. At one point, the atmosphere became so wild that even club bouncers were having a hard time controlling the crowd.

The reports also said that Spears came to the after-party with Jason Trawick, her boyfriend, at approximately 1 a.m. but only stayed at the Factory for 30 minutes. Hip Hop Wired states that Spears and Minaj then performed "Till the World Ends" remix, which features both Ke$ha and Minaj.

Britney Spears' Till the World Ends music video: