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The mastermind behind a string of deadly sniper shootings that terrorized the Washington, D.C. area seven years ago is scheduled to be executed Tuesday night (9:00 pm EST).
John Allen Muhammad is scheduled to be put to death by lethal injection in the eastern state of Virginia for killing a man at a gas station, some 50 kilometers outside of Washington.
Virginia Governor Timothy Kaine denied clemency for the convicted killer Tuesday, clearing the way for his execution. Muhammad's lawyers had asked the governor to commute the sentence to life in prison, saying their client is mentally ill.
Muhammad and his accomplice, Lee Boyd Malvo, killed 10 people during a three-week shooting rampage across Virginia, Washington and nearby Maryland in 2002.
The shootings gripped the U.S. capital area with fear, as victims were gunned down at random while doing everyday chores like shopping or pumping gas.
The U.S Supreme Court rejected Muhammad's final appeal Monday.
The court did not give a reason for its refusal to hear Muhammad's appeal, but three of the nine justices complained that the process had been rushed. They said Muhammad's execution date was set before the court was scheduled to discuss the case.
John Paul Stevens, Ruth Bader Ginsburg and Sonia Sotomayor said Virginia's action highlights "the perversity of executing inmates before their appeals process has been fully concluded."
Malvo was 17 years old at the time of the shootings. He has been sentenced to life in prison without parole in Virginia. The two men also are suspected in several murders in Alabama, Arizona and Louisiana.