The head of a prestigious Boston high school stepped down from her post Tuesday, claiming that she had no control over policies critics say led to racial tension at the school.

In her resignation letter, which was made public Wednesday, former Boston Latin School headmaster Lynne Mooney Teta said she and the school had been "unfairly judged, for reasons that go well beyond the walls of BLS."

The local U.S. attorney's office announced in March it was launching an investigation into allegations of racial harassment and discrimination after community members and civil rights organizations submitted a written complaint.

A school district investigation found that the school failed to adequately respond to a student's threat to lynch a 15-year-old black classmate.

The Boston Herald reported that Justice Department investigators were to hold a summit Wednesday with Boston Latin parents and students about the racial climate at the school. 

Members of Boston's black community said they were "satisified" with Teta's resignation, but claimed issues of "long-term structural inequity" are prevalent throughout Boston's public school system.

"While we recognize that the headmaster was well-meaning and competent in many ways, the environment at the school had grown racially toxic," Darnell L. Williams, president and CEO of the Urban League of Eastern Massachusetts, said in a statement. "It was time for her to step down."

Superintendent Tommy Chang said in a statement that Teta guided students and faculty in creating a more welcoming environment after the allegations surfaced.

Founded on April 23, 1635, Boston Latin is the oldest public school in America. Famous graduates of the school include Samuel Adams, John Hancock and Ralph Waldo Emerson.

The Associated Press contributed to this report.