New data on nearly every public school in the nation shows that students with disabilities continue to be disciplined and experience restraint and seclusion at far higher rates than others.

The figures come from the latest data collection from the U.S. Department of Education’s Office for Civil Rights. It reflects the experiences of more than 50 million students at over 96,000 public schools across the country during the 2015-2016 school year.

The Education Department found that 12 percent of students were served under the Individuals with Disabilities Education Act and another 2 percent under Section 504 of the Rehabilitation Act.

However, students with disabilities were affected by various disciplinary procedures disproportionately. These children accounted for 28 percent of referrals to law enforcement or school-related arrests, 26 percent of out-of-school suspensions and 24 percent of expulsions, the report found.

Meanwhile, the vast majority of the estimated 122,000 students restrained or secluded at school had disabilities, the Education Department said. Children served under IDEA represented 71 percent of those restrained and 66 percent of kids subject to seclusion.

Even with the high number of reports of restraint and seclusion of students with disabilities, concerns have come to light in recent months that schools may be underreporting the practice.

“I am aware of this issue, this claim,” U.S. Secretary of Education Betsy DeVos told lawmakers during a March hearing on Capitol Hill. “We’ll certainly look into ways that we can continue to insist and ensure that states are appropriately addressing and reporting these situations.”

Separately, the latest civil rights data also indicated that just over 1 in 10 allegations of harassment or bullying that schools received were based on disability, while students with disabilities accounted for a quarter of those disciplined for harassment or bullying.

Denise Marshall, executive director of the Council of Parent Attorneys and Advocates, said the findings from the civil rights data are concerning.

“(It) seems clear that our kids continue to be harmed by the failure of the Department (of Education) to take action to address the gross inequities and disparity in treatment,” she said. “How many more generations will it take?”