"You're all invited. Be there or be square," the singer tells fans over Twitter

By Mark Gray
March 25, 2011 01:05 PM

She’s baaaack!

Britney Spears is headed to Las Vegas Friday to perform a mini concert at Palms Casino Resort’s Rain Nightclub, which will be filmed for an upcoming MTV special.

Spears, 29, took to Twitter Friday morning to confirm the rumors that she’ll indeed be onstage in Sin City.

“Looks like my little secret isn’t a secret anymore,” Spears Tweeted, before asking who of her more than 7 million Twitter followers will be attending. “You’re all invited. Be there or be square bitch!”

RELATED: Britney Spears Raves About Jason Trawick’s ‘Ripped Abs’

Hotel and nightclub executives have been tightlipped about what the show will entail, but PEOPLE has learned that Spears will take to the stage twice Friday – once at 8 p.m. in a ticketed event, then again at midnight for a performance that will be open to the public.

The appearance in Sin City comes just days before the release of Spears’s new studio album, Femme Fatale, which will debut Tuesday.