Sean "Jay-Z" Carter and Sean "Diddy" Combs are accused of raping a then-13-year-old girl at an afterparty following the 2000 MTV Video Music Awards, according to an amended civil lawsuit filed Sunday.

"Another celebrity stood by and watched as Combs and Carter took turns assaulting the minor," the lawsuit said without naming the celebrity.

Jay-Z was added to the lawsuit that was originally filed in October as one of several anonymous complaints by Texas attorney Tony Buzbee.

Many of the lawsuits did not survive because the plaintiffs declined to be named but, in this case, the judge said the then 13-year-old showed sufficient cause to continue anonymously.

Carter was identified in the original complaint as Celebrity A.

The plaintiff alleged she was noticed by a limousine driver who invited her to the afterparty where Combs and Carter raped her.

There was no immediate response from Carter's representatives.

This is a developing story. Please check back for updates.