By Karen Brooks and David Schwartz
AUSTIN/PHOENIX, Texas (Reuters) - A Texas inmate who was convicted of killing his parents in 1998 and blowing up their home in Lubbock was executed on Wednesday with a controversial lethal injection drug, hours after Arizona put to death an inmate convicted of strangling an elderly man 35 years ago.
Michael Yowell, 43, was pronounced dead at 7:11 local time at the state prison in Huntsville, Texas, Jason Clark, spokesman for the Texas Department of Criminal Justice, said in a statement.
Clark said Yowell was the first inmate in Texas to be executed using compounded pentobarbital, a barbiturate.
Pentobarbital has become scarce over the past couple of years as major manufacturers have refused to supply it for executions.
Some states have turned to other suppliers such as lightly regulated compounding pharmacies to secure drugs, raising fears among death penalty opponents that use of the alternative drugs will lead to a botched execution.
Yowell had asked a federal appeals court to stop his execution in part because Texas turned to a compounding pharmacy for pentobarbital after its supply expired in September.
Compounding pharmacies, which combine or alter drugs typically to meet an individual prescription for a patient, have also come under strong criticism since a meningitis outbreak last year.
Yowell argued in part that using drugs from a compounding pharmacy and not a manufacturer raised the risk of defective ingredients that could cause him pain in violation of the U.S. Constitution's ban on cruel and unusual punishment. A federal judge rejected that argument.
Prosecutors say Yowell confessed to fatally shooting his father after the older man caught him stealing his wallet to obtain money for drugs. He then beat and strangled his mother, according to the Texas Attorney General's office.
"Yowell said that afterwards, in a panic, he ran to the kitchen and opened a gas jet," the account said. His grandmother, who also lived in the home, was killed in the blast. He was not convicted in her death.
ARIZONA EXECUTES OLDEST INMATE
In Arizona, a death row inmate convicted of strangling a 74-year-old man and fleeing in the victim's Cadillac more than three decades ago was executed by lethal injection on Wednesday.
Edward Harold Schad, who at 71 was Arizona's oldest death row inmate, was pronounced dead at 10:12 a.m. local time at Florence State Prison, Arizona Attorney General Tom Horne said.
Schad was convicted of killing Lorimer Grove in 1978 and leaving his body in some underbrush near Prescott, Arizona, with a rope still knotted around his neck, officials said.
"Well, after 34 years, I'm free to fly away home. Thank you, warden. Those are my last words," Schad said immediately before he was put to death, according to Doug Nick, a spokesman for the Arizona Department of Corrections.
Schad's attorneys had sought unsuccessfully to delay his execution because Arizona had not provided information about the drug to be used in carrying out the execution.
Arizona answered that challenge by disclosing that it had purchased pentobarbital from Lundbeck LLC, a Danish pharmaceuticals company that no longer sells the drug for executions.
Present for the execution were Schad's attorney and a member of the clergy, as well as two media witnesses and prison officials, Nick said. None of Schad's family members attended, nor did relatives of the victim.
The condemned man's last meal consisted of a meatball sandwich, French fries with ketchup, corn on the cob, cranberry sauce, apple pie and a vanilla milkshake, Nick said.
Schad became the first person executed in Arizona in 2013 and Yowell became the 14th to be put to death in Texas. Wednesday's executions brought to 30 the number of people executed in the United States this year.
(Reporting by Brendan O'Brien in Milwaukee, David Schwartz in Phoenix and Karen Brooks in Austin, Texas; writing by Dan Whitcomb; editing by Cynthia Johnston, Gunna Dickson and Matthew Lewis)