Credit: Splash News

Brit's Back! 

In a sexy leather bodysuit, Britney Spears thrilled more than a thousand fans with a surprise mini-concert at the Rain Nightclub in the Palms Las Vegas Friday night.

With back-up dancers clad in army fatigues, Spears, 29, debuted songs from her upcoming Femme Fatale album, including "Hold it Against Me," "Till the World Ends," and "Big Fat Bass." It was the first live show for the mother of two since her 2009 Circus Tour.

"We are extremely excited to have one of the most iconic artists of all time back at the Palms," owner George Maloof told in statement. "Britney's performances were unbelievable and her fans will never forget this night."

The show wasn't a complete surprise. After rumors began circulating yesterday, the singer wrote on her Twitter page: "Looks like my little secret isn't a secret anymore... You're all invited. Be there or be square b****!"

Femme Fatale drops next Tuesday.