During a heated argument that allegedly resulted in the actor severing his finger,
Johnny Depp reportedly accused Heard, 30, of cheating on him with Thornton, but a source tells PEOPLE that is simply not true.
“Billy Bob definitely, absolutely did not have an affair with Amber,” says the source.
The accusation comes as a new photo claims to show Depp’s butchered finger alleged injured during an altercation with his estranged wife in March 2015 while they were living in Australia.
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After the injury, Depp, 53, allegedly dipped his finger in a jar of paint and wrote various messages on a mirror including “Billy Bob” and “Easy Amber.”
Heard and Thornton, 61, starred together in the still-unreleased thriller London Falls. The actress also adamantly denies having an affair, according to TMZ.