John Allen Muhammad, the man who masterminded a series of sniper attacks in the Washington, D.C. area, was executed Tuesday night by lethal injection.

His attorney said his client was fearless in the final hours before his death, and had no final comments.

Muhammad died at 9:11 p.m., prison spokesperson Larry Taylor said.

Muhammad spent the evening with relatives prior to his execution.

"We extend our condolences not only to the families and loved ones of the victims, but also to the family and loved ones of John Allen Muhammad," his lawyer, J. Wyndal Gordon, said. "It's just a tragic situation all around."

Muhammad expressed no regrets for the killings that paralyzed an entire city with fear in 2002, Gordon said earlier.

"He is absolutely unafraid and he will die with dignity -- dignity to the point of defiance."

Virginia Gov. Timothy M. Kaine denied Muhammad's clemency request Tuesday, setting the stage for for the 48-year-old death row inmate to be put to death inside the Greensville Correctional Center in Jarratt.

Kaine's decision came the day after the U.S. Supreme Court turned down the sniper's final appeal on Monday.

The execution came years after Muhammad was convicted for killing Dean Harold Meyers at a gas station in Manassas, Va. The three-week killing spree took the lives of 10 people in total, with victims in Virginia, Maryland and Washington, D.C.

Muhammad also had a teenage accomplice, Lee Boyd Malvo, who was convicted and sentenced to six life terms.

Victims were often shot doing everyday chores like shopping and pumping gas. The indiscriminate and random nature of the shootings left the Washington area on edge until the two shooters, Malvo and Muhammad, were caught on Oct. 24, 2002, while they were sleeping in a car at a Maryland rest stop.

Malvo and Muhammad were also suspected of killing other people in Louisiana, Alabama and Arizona.

Cheryll Witz said she had intended to attend Muhammad's execution on Tuesday.

Her father, Jerry Taylor, was shot dead on a Tuscon, Ariz., golf course in March 2002 -- a murder that Malvo said he committed under the direction of Muhammad.

"He basically watched my dad breathe his last breath," Witz said. "Why shouldn't I watch his last breath?"

With files from The Associated Press