Federal inspectors conducted an unannounced visit of an immigration detention center in southern California and found “serious violations” throughout the facility, where guards improperly placed adult inmates in disciplinary segregation and ignored more than a dozen “nooses” fashioned out of bedsheets.

The report, conducted by the Department of Homeland Security's Office of Inspector General, also showed that medical staff at the Adelanto, Calif., facility disregarded federal regulations governing the treatment of inmates by doing only cursory checks of inmates and making them wait months, sometimes years, to receive basic dental care, leading to tooth loss and "unnecessary extractions."

The report focused on the Adelanto ICE Processing Center, which is overseen by Immigration and Customs Enforcement but operated by the GEO Group, one of the nation’s largest private prison contractors.

"ICE must ensure the Adelanto Center complies with detention standards to establish an environment that protects the safety, rights, and health of detainees," the report concluded. "Mitigation and resolution of these issues require ICE’s immediate attention and increased engagement with the center and its operations."

In her response to the Inspector General report, Nathalie Asher, executive associate director of ICE's Enforcement and Removal Operations, acknowledged that she was "concerned" by the findings. She said the treatment of detainees is "paramount" and announced that the Adelanto facility will undergo a more thorough inspection starting Oct. 10.

After a summer when much of the country’s attention was focused on the treatment of families and minors temporarily held in chain-linked holding pens along the border, the Inspector General report highlights the treatment of adult immigrants in long-term detention.

Immigration and Customs Enforcement oversees 180 facilities — some operated by ICE, some run by private contractors — to house people charged with immigration violations.

Rep. Ted Lieu, D-Calif., visited Adelanto in August and said inmates complained about their medical care, ability to meet with lawyers, and retribution for raising such concerns with members of Congress. On Tuesday, he said the Inspector General report raises even more concerns and shows that he didn't see the "full scope" of problems since officials there knew he was coming ahead of time.

"This OIG report sheds light on the Trump administration's immoral immigration policies and underscores the human toll of Trump's compassionless treatment of immigrants and immigrant detainees," he said.

The Adelanto facility, which uses more than 300 guards to monitor up to 1,900 inmates, was also facing scrutiny from immigration advocates who have been trying to sound the alarm over a series of inmate deaths at the facility. The report found that three inmates have died there since 2015, and that seven inmates attempted suicide between December 2016 and October 2017.

Yet during their visit, federal inspectors saw bedsheet "nooses" hanging from vents in 15 of the 20 cells they observed during their visit. Inmates told inspectors the bedsheets are used as clotheslines and unfurled to create privacy next to the toilet, but are also used in suicide attempts. The contract guards overseeing that section of the detention center told Inspector General staff that the "nooses" are a daily occurrence and are not considered a "high priority."

"ICE has not taken seriously the recurring problem of detainees hanging bedsheet nooses at the Adelanto Center; this deficiency violates ICE standards," the report found.

The report also questioned the use of "disciplinary segregation" at Adelanto.

Inspectors found that guards routinely removed inmates from the general population before a disciplinary panel rules whether the inmate is guilty of the alleged violation. Guards also punished inmates by forbidding them from buying items in the center's commissary and limiting their family visits, both of which should have been ordered by a disciplinary panel, not unilaterally by guards.

"These violations pose a significant threat to maintaining detainee rights and ensuring their mental and physical well-being," the report found.

In her response, Asher said its sometimes necessary to remove an inmate from the general population "to ensure the safety and security of the facility." In those cases, she said inmates are placed in "administrative segregation," which is less restrictive.

The federal inspectors also witnessed a lackadaisical approach to health care in Adelanto. ICE standards require that medical staff conduct "face-to-face medical assessments" of each inmate held in segregation each day. But during their visit, the inspectors saw two doctors simply walking past most cells, peeking inside, and stamping their name on the detainee records hanging outside each cell "indicating that they visited with the detainee."

In one case, the inspectors realized that an inmate had been sitting in a wheelchair in his cell for nine days without once being lifted up to sleep in the bed or brush his teeth. "We saw that the bedding and toiletries were still in the bag from his arrival," the report read.

Inspectors also questioned the dental care being received by inmates. ICE requires that all inmates receive a dental exam within six months of being in detention. But the inspectors found that the two dentists at Adelanto hadn't conducted a cleaning or filled a single cavity in nearly four years.

"Records indicated and center staff corroborated that the center was waiting for detainees to leave rather than provide cleanings," the report read.

One of the dentists said he only provided "palliative care" and doesn't have time to do complete cleanings and fillings. He said fillings aren't necessary if inmates maintain a strict regime of brushing and flossing. When told that dental floss must be purchased by inmates, the dentist suggested "detainees could use string from their socks to floss if they were dedicated to dental hygiene."