"Jay Z was ferociously assaulted by Beyonce's sister Solange ... who was wildly kicking and swinging at him inside an elevator ... and the attack was captured on surveillance video ... obtained by TMZ.
According to our sources, it all went down at a Met Gala after party last week at the Standard Hotel in NYC. In the video ... Jay Z, Beyonce and Solange step into the elevator ... and then Solange goes crazy, screaming at Jay before unleashing a violent attack.
A large man -- who appears to be a bodyguard -- attempts to hold Solange back, but she manages to connect at least 3 times. At one point Solange throws a kick and Jay grabs her foot, but never attempts to strike her. Beyonce stands by without getting physically involved.
- TMZ