Jay-Z got attacked by Solange Knowles because he wanted to go to Rihanna's party according to the New York Daily News. The attack was caught on video and released by TMZ on Monday. The video went viral, along with the hashtag #WhatJayZSaidtoSolange on Twitter.

Solange Knowles' attack on Jay-Z was apparently caused by the rapper saying he was going to go to Rihanna's party without Beyonce.

Jay-Z's attack from Knowles in an elevator at the Standard Hotel in New York City had some follow up events to it. A group of Solange Knowles' non-celebrity friends showed up uninvited to the after party for the Met Ball, a source told the New York Daily News.

"Two of her friends, who were not dressed for the Met Ball, showed up at The Standard and caused a scene downstairs," the source said.

"They wouldn't leave and kept name dropping Jay Z. They were pretending they were guests of his and not hers. Management went to Julius (Beyonce's bodyguard) and said there's a problem."

Jay Z heard about what was happening and said to Solange"don't use my name."

The 27-year-old 'Losing You" singer was hurt by his comment and said she wanted to leave the party.

On the way out, Jay Z said he'd be heading to Up & Down on West 14th Street, where Rihanna was holding her own post-Met Ball bash, a second source told the New York Daily News.

Apparently, Solange was not happy about this turn of events. "She seemed drunk and irritated," said a second source. "She said, 'Why can't you go home?' and to Beyonce 'Why does your husband need to go to the club right now?'"

Jay-Z responded to Solange, "You're one to talk," the source said. Jay's response set Solange into a rage. Once inside the elevator, she started punching and kicking her brother-in-law - an attack that was caught on surveillance video and leaked to TMZ.com on Monday.

Ultimately, Jay-Z decided against going to Rihanna's party and did not attend the soiree.