The head of a New Hampshire prep school's board of trustees says two alumni from the 1970s have filed a complaint against the school alleging they were sexually assaulted as students by former faculty members.

A letter from Archibald Cox to the St. Paul's School community said Wednesday the school is "truly sorry" for their pain, "and for any failure of the school to protect them."

Most of the former staffers named in the complaint were named last year in an investigation conducted by the school into its history of sexual abuse dating to 1947. The school reported allegations against 18 former staffers and shared its findings with the attorney general's office.

Cox said St. Paul's is as committed as ever to "facing squarely the worst elements of our past."