A New York judge has suspended the attorney and an accountant for a late Montana copper mining heiress from administering her $400 million estate.

Manhattan Surrogate Court Judge Kristin Booth Glen on Friday found evidence that Huguette Clark's attorney, Wallace Bock, and accountant Irving Kamsler engaged in tax fraud that resulted in $90 million in unpaid federal gift taxes and penalties. Both deny any wrongdoing.

Kamsler resigned Wednesday from administering the estate.

Clark's family has accused Kamsler and Bock of plundering her fortune. The Manhattan district attorney's office has been looking into how Clark's affairs were managed in the past two decades, people familiar with the probe have said.

The reclusive Clark, a U.S. senator's daughter, was 104 when she died in May.