LAS VEGAS (KLAS) — The convicted murderer who escaped Friday from a prison outside of Las Vegas climbed out of his cell window and over a barbed-wire fence, sources told the 8 News Now Investigators.

Porfirio Duarte-Herrera, 42, was serving a life sentence without the possibility of parole at the Southern Desert Correctional Center for the murder of Willebaldo Dorantes Antonio, records showed. The prison is about 40 miles northwest of Las Vegas in the rural community of Indian Springs.

Duarte-Herrera used acid to help erode the area securing his cell window so he could climb out, sources said. He also created a cardboard dummy to leave in his cell, the 8 News Now Investigators first reported Tuesday.

Duarte-Herrera also sewed a coat in a prison class, which he took with him after his escape, sources said.

Porfirio Duarte-Herrera, 42, is serving a life sentence without the possibility of parole for murder at the Southern Desert Correctional Center, records showed. (NDOC/KLAS)

The 8 News Now Investigators first reported the escape around 11 a.m. Tuesday. It was not until after 1 p.m. that NDOC officials issued a news release on the matter, confirming the 8 News Now Investigators’ earlier reporting.

Corrections officers determined Duarte-Herrera was missing at 7 a.m. Tuesday, officials said in a news release. A search for him began around 8 a.m., NDOC officials said in the release.

The U.S. Marshals had elevated the search to major-case status, meaning nationwide resources were allocated to finding Duarte-Herrera.

Las Vegas Metropolitan Police Department announced Wednesday morning it would assist the U.S. Marshals in attempting to locate Duarte-Herrera. Police said in a Tweet, “He is a convicted murderer and should not be approached. If you see him, please call 911 immediately.”

In a statement issued Tuesday around 5:30 p.m., Nevada Democratic Gov. Steve Sisolak said Duarte-Herrera had “been missing since early in the weekend.” Around 6:15 p.m. Tuesday, NDOC clarified that Duarte-Herrera had in fact escaped Friday.

Duarte-Herrera is described as being 5 feet 4 inches tall, weighing 135 pounds. He has brown hair and brown eyes.