Texas death row inmate Jamaal Howard, 46, who shot a convenience store clerk in 2000, died Wednesday night after receiving a lethal injection, pentobarbital, the same drug used in the botched execution of Tennessee inmate Christa Pike.

Mr Howard, a 20-year-old at the time, killed Vickie Swartout, 42, the clerk at the store. He also stole $114 and a carton of cigarettes. He was convicted of capital murder and subsequently sentenced to death.

Efforts by Mr Howard’s lawyers to stay his execution, predicated on Ms Pike’s case, failed as the U.S. Supreme Court and the Texas Court of Criminal Appeals rejected their prayer.

His lawyers also urged Texas Governor Greg Abbott to pause the execution for 30 days to allow them to gather information on the lethal drug, but he declined.

In his last words, Mr Howard sought the forgiveness of Ms Swartout’s family.

“I wish that you accept my apology, and I wish for your forgiveness,” Mr Howard said. “I’m sorry for what happened. I wish you can learn to forgive me one of these days.”

He also thanked his family for sticking by him throughout the ordeal. He then notified the warden that he was ready for the drug to be administered.

Ms Pike remains alive albeit in critical condition as her lawyers said she suffered pneumonia, blood clot and inability to eat.