Followers of Jennifer Lopez's Instagram were stunned again as the "Luh Yah Papi" singer posted a sneak peek of her new single "Booty." The singer-actress also continued her birthday bash with a surprise celebration from friends.

The 45-year-old pop star posted on Jennifer Lopez's Instagram an artwork emphasizing her much-adored behind, which gives a preview of her coming single "Booty."

The song, which also features rapper Pitbull, also marks her third single from the "A.K.A.," album following the success releases of "I Luh Ya Papi" and "First Love," the Huffington Post said.

Jennifer Lopez's Instagram caption said: "#bootyfromtheblock #bootyandthebeat #naturalbooty #bootybootybootybootybootyeverywhere #jlobooty #LOL."

On Sunday, the "Luh Yah Papi" singer also posted on her Jennifer Lopez Instagram a photo showing her toned body. Jennifer Lopez had joined other Hollywood stars who gamely accepted the ALS ice bucket challenge that raises awareness and funds for Lou Gehrig's Disease.

The singer showed off her sculpted abs as she performed a chilling drill while rocking a black sports bra. She paired her top with low-rise cropped black leggings with a grey waistband and a yellow trainers.

Jennifer Lopez opted to style her hair with a messy up do as she wore a pair of aviator shades.

Meanwhile, the mother-of-two's birthday was two weeks ago but the celebration seemed non-stop, Fox News said.

About 150 close friends of the "Luh Yah Papi" singer have gathered for a surprise birthday bash in a private estate in Calabasas, California.

According to an insider of E! News, Jennifer Lopez was really surprised and happy.

The source added, "You could tell she was touched. She was almost crying."

The insider added that Jennifer Lopez seemed not to have gone through a recent break-up.

"She was out having fun with her good friends," the source said.