At least eight jail staffers were aware that strict instructions had been given not to leave Jeffrey Epstein alone in his cell — but the order apparently was ignored in the 24 hours before he hanged himself, according to a report.

Investigators looking into the apparent failure to follow instructions were shocked that so many Federal Bureau of Prisons staffers — including supervisors and managers — were aware of the directive, people familiar with the matter told the Washington Post.

The sources, who spoke on condition of anonymity, declined to identify the eight staffers.

Investigators suspect that at least some of these staffers also knew that the accused sex trafficker had been left alone in his cell at the Metropolitan Correctional Center before he died — and they are seeking to determine the extent of the knowledge, the sources told the paper.

But they cautioned that the apparent failure to follow instructions does not necessarily rise to the level of criminal conduct — and could be the result of bureaucratic incompetence.

The Bureau of Prisons declined to comment to the Washington Post.

Robert Hood, a former warden at the federal supermax prison in Florence, Colorado, called the matter “perplexing.”

“If people were given instructions that Epstein should not be left alone, I don’t understand how they were not followed,” Hood, a former chief of internal affairs for the Bureau of Prisons, told the paper.

Hood said it was disturbing that officials might have thought they were putting Epstein on a less intensive form of suicide watch.

“You’re either on suicide watch or you’re not. If you have any concern at all, you maintain the suicide watch,” he said.

Epstein, who was found in his cell in July with marks around his neck, was placed on suicide watch, but his lawyers had asked for him to be taken off the watch six days later, and the MCC agreed.

That meant instead of guards checking on him in his cell every 15 minutes, they would now make a pass every 30 minutes — but in Epstein’s case, even that didn’t happen and he hadn’t been checked on for hours before his death.

The two guards who were supposed to check on him during their rounds were asleep at the time, claiming they were overworked. One wasn’t even a full-fledged corrections officer.

The city medical examiner has ruled Epstein’s death a suicide by hanging — a finding not accepted by his lawyers, who said they are conducting their own investigation.

The FBI and the Justice Department’s inspector general also are investigating the case.

The head of the union that represents MCC workers did not respond to requests for comment by the Washington Post.

An FBI spokesman and a spokesman for the US attorney in Manhattan declined comment to the paper.