Carolyn McAtee Cerbin

USA TODAY

The so-called "vampire" killer who said he was taking orders from the devil when he slit the throat of a 12-year-old boy and drank his blood was put to death Wednesday in Texas.

Pablo Lucio Vasquez, 38, admitted in a videotaped confession to police that he smashed David Cardenas' head with a pipe and then slit his throat on April 18, 1998. Vasquez said he tried to cut off Cardenas' head but couldn't get it off.

The scalped, mutilated body was found buried in a shallow grave in the south Texas town of Donna four days later.

Before his execution in Huntsville, Texas, Vasquez was asked by the warden if he had a final statement. Vasquez turned to look through a window where four of his victim’s relatives watched and told them he was sorry.

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“This is the only way that I can be forgiven,” he said. “You got your justice right here.”

Then as the lethal dose of pentobarbital began taking effect, he said he was a little dizzy. “See you on the other side,” he said, raising his head off the gurney pillow and looking toward a window where two of his sisters, a brother-in-law and a cousin watched.

He was pronounced dead 24 minutes later at 6:35 p.m., making him the 11th condemned prisoner executed this year in the USA, six of them in Texas.

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Defense lawyer James Keegan appealed for a stay from the U.S. Supreme Court, claiming problems with jury selection. Keegan previously tried to save Vasquez's life by claiming his client was mentally ill and thus his execution would be a cruel and unusual punishment. A stay was granted, but the argument ultimately failed.

Vasquez said he and cousin, Andres Rafael Chapa, had been drinking alcohol, smoking pot and snorting cocaine when voices told him to kill Cardenas, a friend of Chapa. Vasquez said Cardenas was still alive when Vasquez drank the blood.

“The blood was dripping and (I) got it all over my face. So, I don’t know, I mean something just told me drink," Vasquez told police.

Vasquez, 20 when the murder took place, was sentenced to death in 1999. Chapa, then 15, is serving a 35-year sentence.

Contributing: John Bacon, USA TODAY, and The Associated Press