The Insider.com

Justin Bieber fans were shocked this week when a woman came forward and claimed the teen heartthrob had fathered her child. Some Beliebers have been so outraged they've issued social media death threats against 20-year-old Mariah Yeater, who filed a paternity suit against the pop star.

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So Jimmy Fallon couldn't resist spoofing the teen sensation by offering his own rendition of a new single that Justin could use to put the brakes on the baby daddy drama.

Watch the clip to see Fallon -- complete with flat mop hair, leather jacket and baseball cap -- debut his new hit with the catchy hook: "It's Not My Baby, Baby, Baby, No!"