A Philadelphia prison where two inmates escaped from Sunday night did not have any corrections officers solely watching their housing unit at the time of the escape, nor any on-duty armed perimeter guards when the inmates cut through the prison's exterior fence, according to a correctional officers union official.

The two men, one of whom is facing charges over allegations he killed four people in three different shootings, remain missing as of Tuesday night. They escaped nearly 19 hours before officials discovered they were missing.

Ameen Hurst, 18, and Nasir Grant, 24, escaped from the Philadelphia Industrial Correctional Center around 8:30 p.m. Sunday.

Hurst, who authorities described as "dangerous," was arrested on March 21, 2021, in connection with three separate shootings in Philadelphia spanning from December 2020 to March 2021 in which four people were killed. Grant was in custody on conspiracy drug charges and conspiracy weapons charges.

TWO PHILADELPHIA INMATES ESCAPE PRISON WITHOUT NOTICE FOR NEARLY 19 HOURS; ONE CONSIDERED ‘DANGEROUS’

Ameen Hurst, 18, and Nasir Grant, 24, escaped from the Philadelphia Industrial Correctional Center around 8:30 p.m. Sunday. (Philadelphia Prisons Department)

David Robinson, who serves as president of the public service employees union’s District 33 Council that represents the correctional officers, said Philadelphia Prison Department is understaffed so armed perimeter guards have not been on duty during that specific nighttime shift for eight or nine months.

Typically, two corrections officers would be assigned to each housing unit when the prison is fully staffed, but recent staffing shortages meant the prison regularly only had one officer assigned to housing units.

Robinson said on the night Hurst and Grant escaped, one officer was assigned to monitor multiple units. He said this is usually because other officers fail to report to work or the prison reaches critically low staffing levels.

"I've been talking about the staffing and safety issues for years and seemingly being ignored. I've been saying how something is going to happen, and now that something has happened, so are you listening now?" Robinson said. "Of course, I'm not saying that the commissioner took a key and let them out, but vital posts were cut that could have prevented this."

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The executive staff of the department said in a statement Tuesday that it "categorically denied" accusations that the executive office had closed posts due to a staffing shortage and that those closures led to the escape.

Philadelphia Prisons Department Commissioner Blanche Carney said during a news conference Monday night that prison staff did not learn about the escape until around 3 p.m. Monday. Headcounts at 11 p.m. Sunday, 3 a.m. Monday and 7 a.m. Monday reportedly showed all prisoners were accounted for, even though video footage of the escape showed the two men were gone.

Hurst and Grant escaped the prison by cutting a hole in a fence surrounding a recreation yard, according to the department.

Hurst, 18, and Grant, 24, escaped the prison grounds through a hole cut in a fence surrounding a recreation yard. (iStock)

"We have protocols in place and those protocols were not followed," Carney said at the news conference Monday. "That yard should have been secured, and the fence not breached."

City officials said they were investigating what protocols were not followed and how counts did not reveal the missing inmates until the next day.

Robinson and others, including prison monitors, have complained about the worsening staffing levels and the dangerous situations that could result from it. The department is reported to be down around 800 officers, which is about 40% below the city-approved deployment plan to safely cover the jails that house about 4,300 people.

"Those vacancies put a huge stress on the officers present and on the day-to-day function of the jails," said Noah Barth, the prison monitoring director for the Pennsylvania Prison Society. PPS is an independent organization that monitors conditions in jails and prisons in the state, and pushes for humane conditions for the incarcerated.

The inmates escaped nearly 19 hours before officials found out they were missing. (Google Maps)

Barth said he did not have access to the staffing logbooks, but that monitors for the society had previously reported issues with alleged falsifications in the recreation logbooks and in laundry logs.

Multiple inmates in different units also said they were forced to sign the recreational time logbooks, but were not given that time out of their cells, according to Barth. The prisoners said guards told them their phone privileges would be taken away if they complained.

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Most of the society's reports and recommendations have prompted denials from department leaders, Barth said, adding that new officers have to work extended overtime shifts because of staffing shortages.

Robinson said the council issued a no-confidence vote on Carney last week, and membership came to a unanimous vote.

The Associated Press contributed to this report.