STOCKHOLM • The Twitter-verse is all at witter after American rocker Lenny Kravitz burst out of his pants at a gig at Stockholm's biggest theme park on Monday.

His leather pants split open during an energetic rendition of American Woman and a not-safe-for-work photo of it has gone viral.

As the Swedish edition of the website The Local describes it, "the audience went nuts".

The 51-year-old reportedly left the stage after the expose and then re-emerged, manhood safely back under wraps, to tell the crowd: "Sorry, I ripped my trousers."

The Grammy winner addressed the wardrobe malfunction on Tuesday night by posting a screenshot of a message from Aerosmith frontman Steve Tyler: "Dude...No underwear and pierced... F*** me... You never showed me that s***"

Kravitz's tag #penisgate is trending on social media.