Muhammad was sentenced to death for killing Dean Harold Meyers at a Manassas gas station during a three-week spree that left 10 dead across Maryland, Virginia and Washington, D.C.
The motive for the shootings remains murky. Malvo said Muhammad wanted to use the plot to extort $10 million from the government to set up a camp in Canada where homeless children would be trained as terrorists. But Muhammad's ex-wife has said she believes the attacks were a smoke screen for his plan to kill her and regain custody of their three children.
For the families of those killed, the day is a long time coming.
Cheryll Witz is one of several victims' relatives who were going to watch the execution. Malvo confessed that, at Muhammad's direction, he shot her father, Jerry Taylor, on a Tucson, Ariz., golf course in March 2002.
"He basically watched my dad breathe his last breath," she said. "Why shouldn't I watch his last breath?"
The shootings terrorized the Washington region, with victims gunned down while doing everyday chores like shopping or pumping gas. People stayed indoors. Those who had to go outside weaved as they walked or bobbed their heads to make themselves less of a target.