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RICHMOND, Va. (AP) — Virginia has executed a convicted serial killer who claimed he was intellectually disabled.

Alfredo Prieto was pronounced dead at 9:17 p.m. on Thursday at the Greensville Correctional Center in Jarrat.

The 49-year-old had fought to prove that he’s intellectually disabled to bar the state from putting him to death. But a federal appeals court in Virginia upheld his death sentence in June and the U.S. Supreme Court refused Thursday to block his execution.

Prieto was sentenced to death in Virginia in 2010 for the rape and murder of 22-year-old Rachael Raver and the slaying of her boyfriend Warren Fulton III more than two decades earlier.

The El Salvador native had already been on death row in California for the rape and murder of a 15-year-old girl at the time.

Prieto thanked his lawyers, supporters and family members before mumbling, “Get this over with.”

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