The Standard Hotel is now investigating how footage leaked from an apparent physical encounter between Solange Knowles and her brother-in-law Jay Z in one of the hotel's elevators at a Met Gala after-party.
The more than three-minute TMZ video shows Solange, 27, apparently yelling at, kicking and hitting Jay Z, 44, while a security guard restrains her.
Beyonce, 32, remains stoic throughout the majority of the video, though she does step in between the two shortly before the elevator doors open.
"We are shocked and disappointed that there was a clear breach of our security system and the confidentiality that we count on providing our guests," The Standard Hotel said in a statement to ET. "We are investigating with the utmost urgency the circumstances surrounding the situation and, as is our customary practice, will discipline and prosecute the individuals involved to our fullest capacity."
Beyonce, Jay Z and Solange all attended the Met Gala on May 5, 2014 before heading to The Standard Hotel in New York. During the star-studded fashion event, there were no signs of tension between the three, though Jay Z left in a separate car from Beyonce and Solange following the elevator incident.
Reps for all three stars have yet to comment.
Watch the video below to see the shocking encounter go down.