A civil rights group representing families of four 12-year-old girls who claim they were strip searched for drugs in school is demanding an apology and other measures from an upstate New York school district.

The NAACP Legal Defense Fund sent a letter to the Binghamton City School District on Thursday. It says actions by a middle school principal and nurse on Jan. 15 violated the constitutional rights of the girls, who are black.

The district has said the girls had a medical evaluation but weren't strip searched. It has hired a law firm to investigate independently.

Gov. Andrew Cuomo has asked the state Education Department for a probe. The School Administrators Association of New York State is asking the community to reserve judgment until the investigations are completed.