VERONA, Va. >> Guards at a juvenile detention center for troubled immigrant teenagers had many ways of handling serious problems. At times, they resorted to the chair. Other times, the mask.

According to migrant teenagers and a former worker, the high, hard-backed metal chair had wheels so it could be tilted and moved like a dolly through the halls of the Shenandoah Valley Juvenile Center, a northwest Virginia facility that houses American and unauthorized migrant youths who have emotional, behavioral and psychological issues.

Teenagers as young as 14 were strapped to the chair — some stripped down to their underwear — with their feet, arms and waist restrained by cushioned leather straps and loops, they said.

Those who guards feared might spit on staff, said one former worker, got the mask — a mesh hood that covered their entire faces and heads. Sometimes, the detainees said, they were forced to wear it while in the chair.

Uses of the chair and mask are among the more extreme examples of complaints that have emerged from inside a handful of detention centers that house teenage migrants with a history of violence, mental health problems or, in some cases, gang affiliation. A few hundred a year are held in this separate network of jail-like facilities that also hold American juveniles who have been sent there for a range of behavioral issues and crimes, including assault and murder.

The centers have tougher security measures than the immigrant-only shelters where a vast majority of the migrant teenagers are sent after entering the country illegally, either on their own or with their families.

For years, the government has sent the most troubled migrant youths to these more restrictive facilities, and many complaints about these sites came well before the Trump administration’s crackdown on illegal immigration. Others, though, have been lodged in the wake of the recent surge of detained immigrant children and teenagers, accusations that include use of the restraint devices, injections of psychotropic drugs and long periods in solitary confinement.

In sworn statements at the center of a class-action lawsuit against the Shenandoah Valley facility and the government commission that receives millions of federal dollars to run it, six former detainees paint a hellish portrait of daily life inside.

“They locked me in a room that was 8×10, or maybe 8×16, for 23 hours a day, all by myself,” said one detainee identified only as R.B. in the suit. Originally from Guatemala and now 18 and living with his mother in Texas, he had a pre-existing mental illness and was transferred to the Shenandoah Valley facility because of “behavioral problems,” according to the lawsuit. He said he often got into fights with other detainees and guards because he felt so isolated and angry over his fate. Punishment was the chair and mask, he said.

The Pattern of Allegations

Every year, according to federal figures, between 25,000 and 60,000 immigrant children who are without a parent or guardian are apprehended at the southwest border. A vast majority, including those separated from their families, are sent to federally financed shelters across the country, while a smaller number are found to have emotional disorders or other mental health and behavioral issues and are sent to more specialized facilities, such as the Shenandoah Valley center.

Of the more than 100 migrant youth sites overseen by federal officials in 17 states, about 15 are known as residential treatment centers, staff-secure facilities and secure facilities. The local, state and federal standards and policies by which they must abide vary by state.

Most of the centers existed long before unaccompanied migrant youths began flooding the border: They originally were opened to hold emotionally disturbed and convicted American juveniles brought to them by the criminal justice system. But as the number expanded beginning about six years ago, many won federal contracts to also treat immigrant children, and have done so while continuing to hold local teenagers.

These restrictive detention centers are challenging to run in the best of circumstances and can present dangers to the detainees and employees. One former Shenandoah employee said in an interview that fights between detainees in rival gangs were common, and another former worker said he was jumped and struck repeatedly by several juveniles at once.

Kenneth J. Wolfe, a spokesman for the Administration for Children and Families, which oversees the Office of Refugee Resettlement — the agency responsible for the care and housing of migrant youths — said in a statement that federal officials take appropriate action when there are allegations of abuse.

“Our office also conducts federal monitoring visits and medical reviews, and takes seriously the responsibility of caring for each child,” Wolfe said.

‘They Had Me in That Chair’

Far north of the border where they were first apprehended, in the verdant Shenandoah Valley west of Charlottesville, detainees at the center of the lawsuit described being beaten while handcuffed, slammed against walls, stabbed with pens, subjected to anti-Latino and other racist remarks, and forced to spend hours strapped to the restraint chair.

In interviews, two former employees of the Shenandoah Valley facility, which has received $31.4 million in federal contracts since 2009, said the use of the chair and the mask was carefully monitored, and they were used only as a last resort. They disputed any suggestion that their treatment of the migrant youths was abusive, cruel or unlawful.

But detainees in the lawsuit said that the chair was used often on them and other children, and that they were tied to it for varying lengths of time, from 30 minutes to — in at least one case — 2 1/2 days.

“They had me in that chair for a good hour, but they don’t check the time,” said a former detainee identified by the initials of D.M., a Honduran who was apprehended after he illegally crossed the southwest border when he was 15, and has bipolar disorder and other mental health issues. He was detained at the Shenandoah Valley site starting in 2014 and said he was there at least 11 months.

The class-action lawsuit was filed late last year by the Washington Lawyers’ Committee for Civil Rights and Urban Affairs on behalf of three plaintiffs who were asking for quality treatment and mental health care for all detainees. Since then, two plaintiffs were returned to their home countries and a third decided not to proceed. A fourth migrant teenager who has been detained at the center since December — a 17-year-old boy who he said left Honduras after a gang threatened to kill him if he didn’t join it — was recently added to continue the suit. Three former detainees, including D.M., gave sworn statements about their treatment at the Shenandoah Valley center, but are not plaintiffs.

After news reports in late June about abuse allegations, Gov. Ralph Northam, a Democrat, ordered officials at two state agencies to investigate the claims in the lawsuit. Officials and a child protective services worker interviewed all detained migrants and reviewed their case files.

The detention center — operated by the Shenandoah Valley Juvenile Center Commission, a three-county, four-city agency — said in a statement that it “takes all allegations of misconduct very seriously, including the complaints of abuse described in the pending federal lawsuit.” The center concluded, after a thorough investigation, that the allegations lacked merit.

As of late June, 22 of the facility’s 58 beds were occupied by immigrant youths. In congressional testimony earlier this year, Kelsey Wong, a program director, said the center serves an average of 92 migrants every year, and about 300 youths in total.

Critics have called the restraint chair the “Devil’s Chair,” and a 2009 report prepared for the Annie E. Casey Foundation began by showing the visual similarities between a restraint chair at a juvenile detention center and one used at the Abu Ghraib prison in Iraq.

“It’s not something that has any place at all, in our view, in a well-run juvenile facility,” said Jason Szanyi, deputy director of the Center for Children’s Law and Policy, who has worked with officials in more than 100 juvenile detention centers around the country.