Britney Spears was surprised with a cake and serenaded by fans as she celebrated her 35th birthday during a gig on Friday night.
The pop star was performing at KIIS FM's Jingle Ball at the Staples Center in Los Angeles when host Ryan Seacrest organized a special treat for the Womanizer hitmaker.
Britney treated the crowd to some of her hits on Friday, including Baby, One More Time, Stronger, I'm A Slave 4 U, and Toxic, showing off her impressive figure in a lacy white crop top with feathered sleeves, black shorts, fishnet tights and thigh-high boots.
She also performed tracks from her new album Glory, and brought out R&B singer Tinashe to sing the track Slumber Party live for the first time.
In the middle of her set, Jingle Ball host Seacrest appeared onstage to surprise the singer with a three-tiered black and pink birthday cake, featuring a giant 'B' on top, as her dancers and the crowd sang Happy Birthday.
"Thank you for the sweet birthday wishes!" Britney later posted on Instagram. "Had an amazing day. Love you all."
Moments before the big surprise, Seacrest told Entertainment Tonight he had something up his sleeve for his friend Britney. "It's her birthday, so when you have a birthday, you have to get something with your birthday. It's one of the two things - a present or a cake," he teased.
"It's not a present, it is a cake, but don't tell her!" he laughed. "I'm going to try and get the whole place to sing."
Other performers at Friday night’s gig included Justin Bieber, Fifth Harmony and Bruno Mars.
Earlier on Friday, friends and family took to social media to wish the pop star a happy birthday. Sister Jamie Lynn shared a sweet throwback picture of the mother-of-two on Instagram, captioning it, "Happy Birthday to my big sister. Love you very much."