CHICAGO (CBS) — A second Cook County Jail inmate has died after testing positive for the coronavirus.

Leslie Pieroni, 51, was pronounced dead Thursday evening at St. Anthony’s Hospital, according to the Cook County Sheriff’s office.

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He had been hospitalized since Friday of last week after testing positive for COVID-19, the Sheriff’s office said. The official cause of death is pending an autopsy, but he is believed to have died of complications from the virus, the Sheriff’s office said.

Leslie Pieroni

Leslie Pieroni (Credit: Cook County Sheriff’s Office)

Pieroni was booked into the jail on Dec. 23, 2018, after being ordered held without bond for an incident the month before when he allegedly sexually abused a boy under 13, the Sheriff’s office said.

He was charged with predatory criminal sexual assault and aggravated criminal sexual abuse, and was already a non-compliant registered sex offender at the time of that arrest, the Sheriff’s office said.

In 2006, Pieroni was sentenced to eight years in prison for criminal sexual assault involving two children. He was also charged with failure to register in 2017, and was sentenced to two years’ probation in February 2018, the Sheriff’s office said.

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The first inmate to die of COVID-19 was Jeffrey Pendleton, 59, who was pronounced dead at Stroger Hospital of Cook County at 9:49 p.m. Sunday.

Jeffrey Pendleton

Jeffrey Pendleton (Credit: Cook County Sheriff’s Office)

He had been at Stroger since the Monday before after testing positive for COVID-19, the Sheriff’s office said.

As of 5 p.m. Thursday, there were 276 detainees in custody who had tested positive for coronavirus, of whom 219 were being treated and monitored by the jail’s Cermak Health Services. Pieroni was one of 21 who were being treated at local hospitals, the Sheriff’s office said.

On Thursday, a federal judge denied the request for a mass release of inmates at the jail due to COVID-19 concerns, but ordered Sheriff Dart to implement new safety measures to stop the spread of COVID-19.

The jail has been called the single largest coronavirus hotspot in the country, but Dart claims their numbers are higher because they are testing more aggressively. He said the numbers also include 150 COVID-positive sheriff’s staff‚ some of whom don’t actually work inside the jail facility.

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“They threw in employees who are police officers who have never been in the jail, clerks who have never been in the jail,” he said. “So that’s a bit of a problem. My 5-year-old would have nailed the math a little better than they did.”