An execution by lethal injection was called off in Ohio after officials were unable to find the condemned man's vein.
Alva Campbell, 69, was sentenced to death for the murder of an 18-year-old during a carjacking in 1997.
On Wednesday (local time), an execution team in the state death chamber searched both of Mr Campbell's arms, trying to locate a vein where they could insert an IV to administer lethal drugs. They also searched below his right knee, using a device with a red flashing light.
Some 80 minutes after the scheduled execution, media witnesses observed Mr Campbell shaking hands with two guards. Two minutes later, the witnesses were told to leave, with no explanation.
Later, Gary Mohr, head of the Ohio department of rehabilitation and correction, said he had called off the execution after consulting medical experts. The condition of Mr Campbell's veins meant it was "not likely" a second attempt at injection would be successful, he said.
Mr Campbell suffers from a variety of medical problems, and requires a walker, a colostomy bag and medication to help him breathe. He had previously claimed he was too "too ill" for a lethal injection, and his attorneys suggested he be executed by firing squad instead, as reported by WCPO-TV.
He was wheeled into the death chamber and provided with a wedge-shaped pillow to help him breathe during his execution.
Mr Campbell wiped away tears and shook hands with members of the medical team, after being told his execution had been called off, according to attorney David Stebbins.
"This is a day I'll never forget," Mr Campbell reportedly said.
His execution has been rescheduled for June 5, 2019.