The singer took to the stage at the Sleep Train Arena in Sacramento, California on Tuesday night as pictures emerged of her PDA session with the British actor.
He's meant to be dating Katy Perry, but Orlando was photographed in a red hot embrace with the star as they partied together in Las Vegas in the early hours of Saturday morning .
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Orlando was first linked to Justin Bieber's on-off girlfriend in 2014, and has been pictured getting close to the brunette, who was draped across him as they sat close together in a booth at Light nightclub at the Mandalay Bay.
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In the first picture Orlando can be seen with his arms wrapped around the star, while she leans into his body, their heads dangerously close to each other.
In another steamy picture Orlando can then be seen nuzzling the beauty as she buries her face on his chest, their hands all over each other.
Arriving at around 1 a.m she headed straight to the VIP section of the club with her friends and back-up dancers, according to People magazine, where she was shortly joined by the actor.
They chatted for about 20 minutes and Bloom was spotted kissing Gomez on the cheek, eyewitnesses told the publication, though sources insisted the duo are "absolutely just friends."
After mixing with other partygoers, she returned to sit next to Orlando, who was sipping on a glass of water.
Selena was said to be alone when she went back to her hotel room later in the night, sources insisted.
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There was no sign of Katy Perry at the party. It's believed she's still in a relationship with Orlando and were photographed together at the Met Gala last week in New York - which Selena also attended.
Following the news her ex-husband Russell Brand is pregnant with his first child, we doubt these photos will cheer her up.
Selena and Orlando have been friends for a while and first sparked romance rumoured in 2014 when they were papped looking very suspicious hanging out together in Los Angeles.
After they were spotted jetting to Canada together for such an occasion, Orlando said: “Nah man, we were just attending WE Day.”
This was shortly after Orlando had thrown a punch at Selena's ex Justin during a fight in Ibiza , apparently started over the Sorry star's rumoured fling with his estranged wife Miranda Kerr.
Strangely, Miranda was also in Las Vegas on Saturday night, according to TMZ, where she watched Selena's concert.
Reps for the stars have been contacted by Mirror Celeb for comment.