Three inmates at the Federal Detention Center in Center City filed a proposed class-action lawsuit Wednesday, saying that confining them there during the coronavirus pandemic violates their constitutional rights.

The three, citing preexisting medical conditions that make them especially susceptible to contracting the virus, are asking a federal judge to order the “release of vulnerable persons to home confinement.”

They also asked the judge to order the FDC warden to “mitigate the serious risk” to the remaining inmates and for the appointment of a special master to consider which inmates should be released to home confinement.

Benjamin Geffen, a Public Interest Law Center attorney who helped file the suit, said “hundreds” of the roughly 1,000 people detained at the FDC likely are eligible for home confinement. He said about 800 inmates are awaiting trial, while the rest have been sentenced or await sentencing.

Geffen said he did not know whether any inmates or staff at the center had tested positive for the virus.

“We don’t know of anyone who has contracted it yet,” he said. “We also know the FDC is doing little or no testing there. You’re going to get zero positive results if you do zero tests.”

Geffen called the conditions at the facility at Seventh and Arch Streets “extremely favorable” for the spread of the virus.

“The detainees are crowded two per cell,” the suit says. “Staff members come and go with scant screening for symptoms or personal protective equipment (PPE). Conditions are unsanitary. Detainees have no meaningful ability to take the most fundamental precautions recommended by federal, state, and local officials and public-health experts: social distancing, reducing the number of people with whom one physically interacts, frequent and thorough hand washing, and regular disinfecting of commonly touched surfaces.”

The U.S. Department of Justice on Wednesday announced that its inspector general would check to see whether federal prisons are using best practices to prevent the spread of the virus.

A spokesperson for the Federal Bureau of Prisons declined to comment because the matter is in litigation.

The suit, filed by Timothy Brown, Myles Hannigan, and Anthony Hall, also says the conditions present a danger to the surrounding community because the staff comes and goes, potentially spreading the virus in those travels, and “a sudden surge of inmates needing hospital care” would strain local health-care resources.

The inmates cite outbreaks of the coronavirus at state and federal prisons in Arkansas, New York, Louisiana, Connecticut, North Carolina, and California. In one Arkansas state prison, 43 of 46 inmates in a single housing unit contracted the virus, according to the suit.

The suit also notes that local authorities in some jurisdictions, including Philadelphia, are working to get inmates released to home confinement. And they cite complaints from prison guards, including some in Philadelphia, about conditions while working during the pandemic.

Nationwide, as of Tuesday, 446 federal inmates and 248 staff had tested positive for COVID-19, the Bureau of Prisons said on its website. It listed one case at a residential reentry center on Luzerne Street in North Philadelphia.