An inmate awaiting trial on murder and conspiracy charges used a cellphone to broadcast a Facebook Live video from inside the same Manhattan lockup where Jeffery Epstein hanged himself, The Post has learned.

The shocking breach of security at the federal Metropolitan Correctional Center occurred last month and is part of a large-scale investigation into the use of cellphones by prisoners there, law-enforcement sources said.

Two correction officers pleaded guilty last year to accepting bribes to smuggle cellphones and other contraband into the MCC, where two high-profile prisoners — former CIA computer engineer Joshua Schulte and ex-Westchester County cop Nicholas Tartaglione, a one-time Epstein cellmate — were recently accused of using or possessing cellphones.

“The MCC has more phones than a Best Buy,” one law-enforcement source said.

A 40-second video clip shows Michael Reid, a high-ranking member of the Brooklyn-based “Rockstarz” gang, talking into a phone while shooting a selfie live stream, sources said.

As many as 32 other Facebook users watched his Facebook Live broadcast, which lasted at least 19 minutes, according to information displayed on a computer screen from which it was recorded.

The video is grainy and poorly lit, but appears to show Reid, 26, sitting on the bottom of a bunk bed, underneath a light embedded in a cement ceiling.

Several people can be heard speaking, but the dialogue is unclear and the clip ends abruptly when a cellphone apparently starts ringing.

Reid is one of 10 reputed Rockstarz members who allegedly chased a rival gang-banger — Tyquan Eversly, 21, of the “Very Crispy Gangsters” — through the streets of East New York before one of them fatally shot Eversley when he got tangled in razor wire atop a chain-link fence on March 19.

Surveillance video shows Reid hurling a large rock at the victim before Donaven McDay, 29, opened fire, according to authorities.

Reid was arrested by the NYPD on March 26 while free on a $100,000 bond and wearing a federal ankle monitoring bracelet following his Dec. 7 guilty plea to bank fraud conspiracy in a $140,000 counterfeit-check cashing scheme.

Reid was transferred from Rikers Island to the MCC on July 3 to await a July 30 sentencing in the bank fraud case.

Court records show that his prison term has yet to be imposed, but that Manhattan federal Judge Paul Gardephe intends for him to serve 18 months, “partially concurrent” with whatever time he gets in the murder case.

The BOP has come under fire since Epstein, a wealthy pedophile awaiting trial on child sex-trafficking charges, hanged himself in his cell in the MCC’s Special Housing Unit on August 10.

US Attorney General William Barr reassigned the MCC’s warden, Lamine N’Daye, three days later and last week demoted the BOP’s acting director, Hugh Hurwitz, amid investigations by the FBI and the Justice Department’s inspector general.

As many as 20 MCC employees have also been subpoenaed over allegations that Epstein was able to kill himself because two workers were sleeping on the job, according to reports.

The US Bureau of Prisons, which runs the MCC, declined to comment on Reid’s Facebook Live video or say “whether a specific inmate has a disciplinary history.”

In a prepared statement, the agency also said: “Like all correctional agencies, the BOP continues to tackle the problem of contraband being introduced into our facilities, including contraband cell phones.”

“The BOP continually evaluates and deploys as appropriate, contraband-detecting technologies, including walk-through metal detectors and whole-body imaging devices,” it said.

“In addition, we have employed enhanced staffing patterns in high security prisons as well as strengthened internal security procedures.”