The Roman Catholic Diocese of Norwich is facing 20 lawsuits filed this week alleging abuse of teenage students at The Academy at Mount Saint John, a Deep River residential treatment center, in the 1990s.

The lawsuits were filed by Hartford attorney Patrick Tomasiewicz, alleging students were abuse at the hands of at least four staff members, although the majority of the allegations were against two now-deceased brothers.

The academy used to be a residential boarding school where the state Department of Children and Families and the juvenile courts referred minors. A number of similar lawsuits have previously been filed against the facility.

It is now called The Connecticut Transition Academy for students with special needs and is no longer a boarding school. Students are referred from any school district in the state. The diocese still oversees the academy.

“We represent a lot of people that were harmed and we are going to do our best for them,” Tomasiewicz said.

Norwich Diocese spokesman Wayne Gignac said Wednesday that the church wouldn’t comment on pending litigation.

The bishop of the Norwich Diocese is a member of the Mount Saint John’s board of directors and is responsible for appointing the executive director. The lawsuit said that Bishop Daniel Reilly appointed Brother K. Paul McGlade, who is one of the brothers alleged to have abused the teenagers.

The lawsuits allege that McGlade and other teachers were under the supervision of the diocese and therefore the diocese is liable for their actions — a distinction that the diocese has fought in previous legal actions.

The victims were between 10-15 years-old and the incidents occurred between 1986 and 2000, the lawsuits said.

The lawsuits filed this week alleged abuses mostly by either McGlade or Brother Pascal Alford, one of the school’s music teachers. Two other teachers also were accused in at least one lawsuit.

Neither McGlade and Alford were priests.

One case accusing Alford of abuse involved a 13-year-old who was placed at the academy in 1993 by DCF and soon after began taking trumpet lessons from Alford, the lawsuit said. Alford began touched the boy’s face, the lawsuit says, telling him “professional trumpet players don’t keep their cheeks out.”

Alford eventually fondled the teenager, the lawsuit said. In at least one other case Alford is accused of making a student perform oral sex on him while McGlade was present. The lawsuits allege that on occasion female members of the staff either watched or participated.

In lawsuits that name McGlade, the allegations range from him touching the genital area of an altar boy to performing oral sex on another student.

In one case involving a 13-year-old placed at Mount Saint John’s by DCF in 1992, McGlade asked the teenager if he wanted to be an altar boy for Sunday Mass. The lawsuit alleges that McGlade started off by rubbing the boy’s shoulders and back under his clothing. It eventually escalated into McGlade asking the teenager to perform oral sex on him under the guise that “it was good for God and he would be rewarded.”

In addition to the allegations of sexual abuse, Mount Saint John has a troubled history that included dozens of substantiated cases of abuse and neglect by staff against kids from the late 1990s to about 2011, according to state records.

The school had its licensed capacity reduced by nearly half in 2007 by DCF over concerns about inadequate staffing and physical aggression by both staff and residents there.