Miley Cyrus reportedly had a "complete breakdown" backstage following her tearful performance of new track Wrecking Ball at the iHeart Radio Music Festival, a new report has claimed.

The 20-year-old was said to be incredibly emotional after seeing images of ex-fiance Liam Hemsworth kissing Mexican beauty Eiza Gonzalez just two days after officially confirming a split.

According to eyewitnesses, the former Disney star ran to her mother and hugged her after the number -- and the emotional breakdown continued backstage.

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"She really lost it," an eyewitness told Life & Style. "She was hysterical crying. There were a lot of tears."

As EnStars reported, Hemsworth moved out of the Toluca Lake, Calif., home he shared with her before they announced their split.

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Before the couple had officially called off their engagement, Hemsworth was spotted partying in Las Vegas with Eiza Gonzalez, a 23-year-old actress and singer.

Then, a steamy snap obtained by E! News showed the pair locking lips outside her Beverly Hills apartment.

The hunk reportedly stopped by Gonzalez's home around 3:30 p.m. to give her a piece of luggage, possibly one left at his house after they reportedly spent the night together following a rendezvous in Las Vegas last weekend.

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