PHILADELPHIA (AP) — Four white Philadelphia teachers filed federal race-bias lawsuits that accuse a black principal of creating a hostile work environment and suggesting they were unfit to teach black children.

The teachers work at a predominantly black elementary school that has a recent history of racial tension. Their lawsuits say that a former principal had them read an article that said “white teachers do not have the ability to teach African-American students.”

The teachers also allege that the principal, Charles Ray III, and others undermined their work by reprimanding them, randomly changing their room assignments and letting black teachers ignore rules that their white counterparts had to follow. Ray also retaliated when they filed union grievances, they said.

“Charles Ray III consistently stated that he had a relationship with top school officials indicating that his conduct was part of an approved policy or was part of a pattern of practices sanctioned and supported by ‘higher authority,”’ the suits allege.

The teachers—Nicole Boyd, Debra McKibben Marenbach, Colleen Yarnell and Marta Ciccimaro—filed the lawsuits last week, demanding more than $150,000 each. Courthouse News Service first reported on the complaints Tuesday.

The school district had no immediate comment, spokeswoman Shana Kemp told The Associated Press.

Kemp said she was not immediately authorized to say if Ray still works for the district. A message left at a possible home number for him was not immediately returned.

Racial tensions among staff at Thomas Mifflin Elementary School have simmered before.

A white principal left about four years ago amid a chorus of complaints from black parents. One mother testified at a City Council meeting in December 2007 that she had heard the administrator say Muslim students looked like “flying nuns,” according to news reports.

In April 2008, vandals defaced a mural on the side of the school with anti-Semitic graffiti.

Ray arrived that fall, and lasted only for the 2008-09 school year, the lawsuit said.

The surrounding East Falls neighborhood is largely white and, in some sections, wealthy. Residents include former Gov. Ed Rendell and former U.S. Sen. Arlen Specter. But many white families in the area send their children to private schools.

Mifflin currently has about 270 students, 86 percent of them black and 85 percent of them poor, according to school district data.

The defendants include the local teachers union and a supervising teacher whom Ray allegedly ordered to go through personnel files and investigate their home and personal lives.

Lawyers for the teachers did not immediately return calls for comment.

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