Luxury real estate moguls and their brother pleaded not guilty on Friday to federal sex trafficking charges, while prosecutors said they intended to bring another indictment and have now interviewed more than 60 complainants in the case.

Tal, Oren and Alon Alexander entered their pleas in Manhattan federal court before U.S. District Judge Valerie Caproni. The brothers were arrested in Miami in December, but an unsuccessful bail fight in Florida delayed their appearance in the Southern District of New York.