Serial killer's horror death in botched execution as room had to be cleared

The gas chamber was once the primary method of execution in most US states, but this changed following the death of serial killer Jimmy Lee Gray. Even before his capital crime, Gray was infamous for his violent behaviour and petty crimes.

At just 19, Gray's violent tendencies escalated when he brutally murdered his 16-year-old girlfriend, Elda Louise Prince, in Arizona. Despite the horrific nature of his crime, Gray was released after serving only seven years of a 20-to-life sentence.

Less than a year later, he struck again. On 25 June 1976, three-year-old Deressa Jean Scales disappeared after being left unattended outside for just 10 minutes. While her location remained unknown for some time, it soon became clear that the worst had occurred.

Gray had lured the child into his car, driven to a secluded area, sexually assaulted her, and suffocated her by forcing her face into mud. When questioned by detectives, he broke down in an elevator, exclaiming: "If I take you to her, will you help me?', subsequently leading the police directly to the child's body. So appalling were his crimes that even Gray's own mother pleaded with the courts not to show mercy, writing to authorities imploring them to "show no mercy, reports <a href="https://www.mirror.co.uk/news/us-news/harrowing-botched-gas-chamber-execution-36318922" rel="Follow" target="_self">the Mirror</a>.

"However, nothing could have prepared onlookers for the horrific scenes that unfolded inside the antiquated gas chamber at Mississippi State Penitentiary.

A vertical steel pole stood directly behind the execution chair. Critically, there was no headrest, no restraint, and consequently nothing to prevent Gray's head from striking the metal should he begin to convulse.

At 12:10am, cyanide pellets were released into acid beneath his chair. As the deadly gas ascended, Gray instantly started convulsing with tremendous violence.

His features contorted in torment.His body strained against the restraints. Then, with an abrupt spasm, he hurled his head backward, and commenced repeatedly battering his skull against the metal pole, groaning in anguish with each impact.

With numerous horrified witnesses observing, authorities decided to evacuate the chamber because spectators were unable to endure watching the ordeal.Medical professionals confirmed his heart continued pumping for a torturous 12 additional minutes before he was eventually declared deceased.

A prominent execution specialist subsequently described the technique as "so painful we wouldn't use it on laboratory animals."

Within 12 months, Mississippi proceeded to eliminate gas executions for future sentences.