CONCORD, N.H. (AP) — Ten former workers at New Hampshire’s state-run youth detention center have been formally indicted and in some cases are facing more charges than they did when they were arrested in April.

The men were charged in April with either sexually assaulting or acting as accomplices to the assault of more than a dozen teenagers from 1994 to 2007 at the Youth Development Center in Manchester. The center, now called the Sununu Youth Services Center, has been the target of a criminal investigation since 2019, and more than 300 men and woman have come forward with allegations involving 150 staffers from 1960 to 2018.

A total of 87 indictments were made public Wednesday. While one defendant saw his charges drop from 33 to 23, the grand jury added charges for five others, including Jeffrey Buskey and Stephen Murphy. Prosecutors had brought 82 rape charges against them in July 2019, dropped them eight months later to s trengthen the expanded investigation and then re-arrested them in April. Buskey, who faced five charges at that time, now faces 25; Murphy’s charges now total 15, up from five.

The new charges against Murphy include allegations that he sexually assaulted a boy with a wrench. All but four of Buskey’s charges allege assaults on David Meehan, who has gone public with his claims and has sued the center, the agencies overseeing it and half a dozen former employees. According to the indictments, the abuse included sexually assaulting Meehan at gunpoint at an off-campus home and an incident in which Meehan was punched in the face and held down by another staffer while Buskey assaulted him.

The investigation so far has produced nearly 730,000 pages of juvenile resident records, daily logbooks and other materials from the 1990s alone, and prosecutors are in the process of obtaining records from 1980s and from the last 20 years. In a recent ruling giving the state permission to share most of the records with defense lawyers, Judge N. William Delker described the prosecution’s theory that a “deep-seated culture of abuse and silence” allowed the abuse and prevented victims from coming forward.

“According to the State’s proffer, the atmosphere that facilitated these crimes arose over decades. These defendants learned from their supervisors that it was acceptable to inflict abuse on the children within their care,” he wrote. “The regimented nature of the Youth Facilities and the system of discipline, isolation, and control used on juveniles within the custody of DHHS reinforced a culture of silence.”

Attorney Kirsten Wilson declined to comment on behalf of Trevor Middleton, who is facing two sexual assault charges involving the same teen. Attorneys for the other defendants did not respond to requests for comment.

In addition to the 10 former Manchester workers, an 11th former youth counselor who worked at a Concord pre-trial detention center, also was arrested in April. The grand jury handling that case has not yet handed up indictments.