A convicted murderer who disappeared from a state prison in Arkansas was found Tuesday morning on the roof of the facility where he had been serving his sentence, the Arkansas Department of Correction said.

Officials at the East Arkansas Regional Unit, a 1,650-inmate prison about 110 miles east of Little Rock, realized at 4 a.m. on Monday that the inmate, Calvin Adams, 49, who was serving life without parole, was missing, Dina Tyler, a spokeswoman for the Arkansas Department of Correction, said on Monday.

He was last seen on security footage at 12:15 a.m., she added, but officials were unsure whether he was hiding on the grounds or had actually escaped from the prison, which is in a rural area.

On Tuesday, the department announced on Twitter that he had been found. “He was found about 8:30 this morning,” Ms. Tyler said in an email. “He was on the roof of the prison hiding under a ventilation hood. He never left the property.”