Kourtney Kardashian and Hailey Baldwin Attend Justin Bieber's Wild 22nd Birthday Party

Happy Early Birthday JB! Love you bro #JB22

A photo posted by Alfredo Flores (@alfredoflores) on

Happy birthday to me! Justin Bieber threw himself a wild 22nd birthday party at a Bel Air mansion on Saturday, February 27, with appearances from his rumored flings Kourtney Kardashian and Hailey Baldwin, plus close friends Scooter BraunJoe Jonas, Sean “Diddy” Combs and more.

The “Love Yourself” singer — who officially turns 22 on Tuesday, March 1 — briefly went shirtless at the party before trying on a Bad Boy letterman jacket that Diddy, 46, gave him.

“Had to give lil bro that official #BadBoy Jacket for his Birthday,” the rapper later captioned an Instagram post.

Kardashian, 36, posed for a photo booth shot with some of Bieber’s closest pals, including his best bud Alfredo Flores, who posted the image on Instagram. Sources confirmed to Us Weekly in December that the singer and the Keeping Up With the Kardashians star were hooking up, shortly before he was linked to Baldwin in January.

Eyes closed just slangin' #JB22

A photo posted by Alfredo Flores (@alfredoflores) on

Although guests were asked not to take photos, they were encouraged to use the hashtag #JB22, according to one Instagram user that attended the bash.

That didn’t stop Bieber’s closest friends from sharing pics from the epic night. Flores posted another group shot of himself, Bieber, Braun and Ryan Good with the caption, “Happy Early Birthday JB! Love you bro #JB22.”

Braun, 34, who is also the singer’s longtime manager, 'grammed another photo, writing, “All grown up. Happy bday @justinbieber. Love yah buddy.”

See more photos from the birthday celebration below!

All growns up. Happy bday @justinbieber. Love yah buddy. @justinbieber @yael #jb22

A photo posted by Scooter Braun (@scooterbraun) on

#22 🍰

A photo posted by J O E J O N A S (@joejonas) on

Happy birthday @justinbieber @djtayjames

A photo posted by @nickdemoura on

When you catch the Holy Birthday feels real quick 😂😂 #JB22 | @justinbieber @poobear @sammy 🎥: @taylorcutfilms #rp

A video posted by Alfredo Flores (@alfredoflores) on

BrittanyJFurlan via snapchat

A video posted by Justin Bieber Updates™ (@justinbiebertracker) on

this one might do it @justinbieber

A photo posted by Hayes Grier (@hayesgrier) on

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