WASHINGTON — Lloyd Collins Jones, a state prison inmate convicted of murder, left the East Arkansas Regional Unit on Monday dressed in white and headed to a construction site nearby, under the supervision of armed guards, to labor for a Department of Corrections work program.

Jones, 40, had served just four years of his 60-year sentence for strangling a 16-year-old girl and stuffing her in a barrel, a crime he pleaded guilty to committing in 2012.

At noon on Monday, Jones apparently decided he’d served enough time, and vanished from his captors’ gaze. Authorities have not seen him since.

News of the man’s escape spread quickly online, his description and past convictions shared many times over by police and sheriffs’ departments across Arkansas. The Department of Corrections issued an alert about his escape, which happened in the small town of Brickeys, about 100 miles east of Little Rock, the state capital.

Jones, who had previously served prison time on a 2001 rape conviction, met 16-year-old Angela Allen on a social media website in 2012, reported the Times Record. The two exchanged text messages and on the night of Feb. 10, the last time her family saw her, Allen went with Jones to ‘‘Mud Town Bottoms,’’ an area along the Arkansas River.

They kissed, according to news reports, but Jones became angry when he learned the girl was just 16. He shoved her in the chest, authorities said, and she fell into the water.

Allen’s body was found more than a week later, buried in a blue plastic barrel on a property owned by Jones’s brother, according to news reports. Investigators said the girl was strangled to death.

Jones pleaded guilty to the murder and was sentenced to 60 years in prison. He was also sentenced to 20 years on two child pornography charges and 10 years for one child pornography charge and abuse of a corpse, reported CBS News.

Washington Post