Chris Brown celebrated his 24th birthday – which is actually on May 5th – at the Emerson nightclub in LA on Friday night, with former flame Karrueche Tran but without Rihanna.

The move is sparking rumors that there might be trouble in paradise for Rihanna and Chris Brown once again.

Rihanna, 25, is currently in New York for her Diamonds World Tour, and sources have revealed that work commitments are preventing the couple from finding much time to spend together.

A source told HollywoodLife: “It’s up and down sometimes, the s**t is even sideways. Every time some s**t pops off between them, they blast that s**t all over social media, and they shouldn’t.

“But when they’re far apart, that’s how they act out towards each other when one of them doesn’t get their own way. It’s crazy as f**k, but it’s how they get down.”

Chris Brown celebrated his 24th birthday at the Emerson nightclub in LA with ex Karrueche Tran but without Rihanna

Possibly trying to take his mind off his far-away girlfriend, Chris Brown hit LA to celebrate his upcoming birthday with some famous friends.

The singer was joined by Christina Milian, David Hasslehoff, Chloe Green and ex-girlfriend Karrueche Tran as he partied the night away.

Chris Brown kept it casual for the celebration, wearing khaki-colored chinos and a white T-shirt. He wore an open chequered shirt and completed his look with a pair of black hi-top trainers.

Karrueche Tran – who was dumped by Chris Brown when he got back with Rihanna last year – showed off her slimline figure as she helped her ex celebrate.

Topshop heiress Chloe Green also attended in a white see-through top and leather trousers.

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