John Muhammad and Lee Malvo were moved to the jail in Alexandria where Zacarias Moussaoui, the Frenchman charged with complicity in the September 11 attacks, is held.
Their transfer was ordered by the attorney general, John Ashcroft, who had said earlier that they should be tried where there was the best evidence and the prospect that they would face the "ultimate sanction".
The pair have been charged with shooting 17 people, killing 12 and wounding five, in Maryland, Washington DC, Virginia, Alabama and Washington state. Yesterday the police in Atlanta, Georgia said ballistic evidence tied them to a murder there in September.
Six of the murders were in Maryland, but Maryland has a moratorium on executions and a permanent ban on the execution of minors. Mr Malvo, a Jamaican, is 17.
Virginia has the highest execution rate in the US after Texas - 86 since capital punishment was reinstated in 1976 - and has no ban on executing juveniles. Its prosecutors have said they could use Virginia's terrorism law, which could allow capital charges against an accessory.
It was reported that Mr Malvo will be tried in Fairfax county for killing Linda Franklin, shot while loading her car on October 14, and Mr Muhammad in Prince William's county for murdering Dean Meyers at a filling station five days earlier.
