Steven Ray Thacker, 42, was put to death by lethal injection shortly after 6 p.m. local time in the state penitentiary in McAlester, KTUL-TV, Tulsa, reported. He had waived his right to a clemency hearing and did not try to stop his execution, the TV station said.
Thacker was convicted of raping and killing Laci Dawn Hill, 25, of Bixby, Okla., in December 1999, and he also killed a Missouri man on New Year's Day 2000 and a man in Tennessee the following day.
Members of the victims' families watched Thacker die, WTUL-TV said.
He was not allowed visitors during his final day, but was allowed to make phone calls.
His last meal was a large pizza, a root beer and some chocolate-and-candy-coated peanuts.