The mounting tension between Orlando Bloom and Justin Bieber finally reached a boiling point, according to reports.

The stars were at Cipriani in Ibiza early Wednesday morning, along with a crowd that included Lindsay Lohan, Paris Hilton and Diddy, when Bieber walked past Bloom's table.

That's when, according to a video clip and eye-witness reports obtained by TMZ, Bloom threw a punch at Bieber, who reportedly made a rude comment about the actor's ex, model Miranda Kerr.

Bloom and Kerr reportedly argued in 2012 after Bieber was spotted flirting with Kerr after the Victoria's Secret Fashion Show. The pair, who have one child together, separated in October 2013.

To add fuel to the fire, Bloom was spotted with Bieber's on again, off again girlfriend, Selena Gomez, in April.

TMZ says Bieber continued to taunt Bloom by posting a picture of Kerr after the fight, but quickly deleted it.