PITTSBURGH — A suspended state prison guard was arrested on charges that he sexually or physically assaulted more than 20 inmates — including a transgender inmate and others imprisoned for child-sex crimes — then attempted to cover up his crimes.

Harry Nicoletti, 60, of Coraopolis was in custody Tuesday awaiting arraignment.

The 92 criminal charges filed Tuesday include several counts each of institutional sexual assault, involuntary deviate sexual intercourse, and official oppression — which amounts to covering up the crimes or allegedly threatening others to do so. The criminal charges mirror allegations contained against Nicoletti and officials at the state prison in Pittsburgh in two civil rights lawsuits filed by inmates in recent months.

The lawsuits, one filed in 2010 and another on behalf of an anonymous inmate last week, allege the systematic abuse of inmates — especially those convicted of child sex-crimes, or believed to be homosexual — by Nicoletti and other inmates at his direction. The lawsuits say the abuse occurred over the past two years in the prison’s F Block, a reception area where new prisoners are housed for a few days for medical testing and to receive other supplies before they’re moved to permanent cells.

Among other things, Nicoletti is charged with raping inmates and threatening them with other sexual acts and with having inmates contaminate the food and bedding of his alleged targets with urine and other bodily fluids.

According to the criminal complaint, one of Nicoletti’s victims was a transsexual male who developed female breasts due to hormone treatments. Nicoletti fondled that inmate before raping him, while shouting racial and sexual epithets, including calling him a “weird freaky monkey,” the complaint said.

In another instance, Nicoletti singled out an inmate for abuse by announcing the man’s conviction for a child-sex offense and saying “Make way for the mole,” according to the complaint.

Allegheny County District Attorney’s spokesman Mike Manko said the state Department of Corrections has cooperated in the grand jury investigation that resulted in the charges against Nicoletti, and that more arrests were expected.

“The Department of Corrections does not tolerate violence in its prisons and we will seek prosecution of such acts, and this case sends that strong message,” corrections spokeswoman Susan McNaughton told The Associated Press.

In April, corrections officials suspended eight guards at the prison, including Nicoletti. Four prison officials were removed and have since left the department, though officials have declined to say whether they were fired or resigned.