We’re not really sure what exactly went on during Jennifer Lopez’s 40th birthday party over the weekend, but whatever it was, the big-butted singer/actress didn’t want us to see it. She reportedly instructed security to hold everyone’s cell phones and cameras at the door.

Guests at the party in NY’s Hotel Griffou, included Madonna, Rihanna, Beyonce, Alicia Keys and Mary J Blige.

We’re placing our bets on a massive celebrity orgy.