Complaints of disability discrimination in the nation’s schools are at their highest level in six years, the U.S. Department of Education says.

A newly released annual report shows that the agency’s Office for Civil Rights received 6,749 complaints of disability discrimination during the 2023 fiscal year, which ran from October 2022 through September 2023. That’s up from 6,390 the year prior and is the largest number since 2017 when over 7,200 similar complaints were filed.

The increase comes as the Education Department’s Office for Civil Rights received a record number of complaints overall. The office, which is charged with investigating discrimination based on race, color, national origin, sex, disability and age in programs funded by the Education Department, said it logged 19,201 complaints during the 2023 fiscal year and resolved 16,448 cases.

“The continued need for reminders and enforcement of these core civil rights requirements is disheartening,” wrote Catherine E. Lhamon, assistant secretary for civil rights at the Education Department, in the report. “Yet, school communities’ commitments to right what had been wrong and to support their students’ full and fair access to education inspire me, protect students and fulfill our nation’s highest aspirations for whom we will be.”

Of the disability complaints, the annual report shows that the largest chunk — 2,744 — were related to the right of students with disabilities to receive a free appropriate public education. Other big issues prompting complaints were different treatment, exclusion or denial of benefits and retaliation.

During the 2023 fiscal year, the Office for Civil Rights indicated that it addressed complaints related to timely evaluations, shortened school days, restraint and seclusion, access to athletics, services during the COVID-19 pandemic, accessibility and more.

“I think the increased number of complaints ties directly to the lack of oversight in the states for the implementation of the law,” said Denise Marshall, CEO of the Council of Parent Attorneys and Advocates, or COPAA, a nonprofit that advocates for the rights of students with disabilities and their families. “The fact that states are not holding districts accountable is not new. OCR investigating and issuing resolution agreements is, in my opinion, some of the only accountability happening, especially around segregation, harassment, equity and disability related discrimination.”

Typically, disability complaints account for the largest percentage of those received, the Education Department said, but that was not the case in 2023. That’s because a single individual filed 5,590 complaints of sex discrimination, substantially altering the ratio.

The civil rights office said that its overall complaint volume has nearly tripled since 2009, but its staff has been reduced since that time. Disability and civil rights organizations have been pushing for increased funding for the office to ensure that it can appropriately handle the increased caseload.