Juvenile detention centers in New York are keeping children and young adults in solitary confinement for days or weeks at a time, a federal lawsuit filed Thursday alleges. The facilities lock the youth in small cells without sinks or toilets, often for upwards of 23 hours a day, forcing them to urinate and defecate in bottles, food containers, and garbage bins, according to the lawsuit.

The detention centers routinely use isolation both as punishment and when they’re understaffed, the youth allege. During the lockdowns, the incarcerated young people are often locked in rooms without access to telephones, media, recreational activities, or human contact. Some of the rooms have no windows.

“Anyone who has a child can envision the harmful effects of isolating a youth in a cell,” said Kate Wood, staff attorney with the Legal Aid Society, which filed the lawsuit with the law firm Jenner & Block. She said their clients describe “really losing themselves, drowning in anxiety and fear and total lack of mental stimulation.” Some have threatened suicide, Wood said.

The detention centers, known as secure placement facilities, are operated by the state Office of Children and Family Services, which also runs New York’s foster care, adoption, and child protective services systems. The facilities, which hold young people ages 12–21 who are convicted of crimes in family or youth criminal court, are supposed to focus on rehabilitation and treatment. OCFS policy requires that they offer seven to eight hours of daily educational, vocational, and recreational activities. Instead, according to the lawsuit, they’re frequently locked down, and some have provided little or no classroom education in the last year, even when they haven’t been on lockdown.