Things are about to get tense between Selena Gomez’s new man and her old flame.

A source close to Justin Bieber tells In Touch that he’s ready to take on The Weeknd — and pals fear he’ll attack the singer, 27, if they encounter one another.

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“Justin’s friends are worried that all hell will break loose if he comes face-to-face with The Weeknd,” the source explains, noting the time that Justin got physical with Orlando Bloom over Miranda Kerr (at the time, Orli was also rumored to be pursuing Sel). “History could easily repeat itself with The Weeknd if they end up in the same room.”

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According to another insider, Justin has been “spiraling” for some time now — and it appears he may have finally “snapped.”

“He called Selena several times in mid-February,” the insider confesses. “She told friends that he seems to have snapped.”

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And his behavior seems to justify her suspicions. Several sources tell In Touch that Justin got in “multiple” fights on Feb. 10 while partying at Serafina in LA — with two male patrons, a bartender, and his pal, Kyle Massey, a former Disney Channel star.

“Justin was very drunk and demanding more drinks. He was fighting,” one eyewitness tells In Touch. Another adds, “He was drinking tequila all night. He was out of control.”

Apparently, the 22-year-old isn’t taking news of his 24-year-old on-again, off-again girlfriend love well — especially since he thought they’d always have a future.

“He always thought Selena would carry a torch for him,” the first source explains. “But she’s refusing to be manipulated by him anymore.”

MUST SEE: Selena Is “Feeling Things She Never Felt Before” With The Weeknd

On her end, she’s made it clear that she’s done with the “Sorry” singer with her diss track “It Ain’t Me,” in which she croons, “We stopped seeing eye-to-eye/You were staying out all night/And I had enough.”

Looks like she’s sick of that same old love — once and for all!

Scroll through the gallery below to see our predictions for Selena and The Weeknd’s relationship!

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