A Louisiana grand jury has charged the Washington-area sniper suspects with first-degree murder for a killing in Baton Rouge.
Prosecutors in Washington, DC, have filed their own charges against the pair.
The Louisiana victim, Hong Im Ballenger (45), was shot on September 23rd during a robbery at the beauty products shop she managed.
Prosecutors said they will seek the death penalty for both Mr John Allen Muhammad and Mr John Lee Malvo.
But Mr John Sinquefield, assistant district attorney, said he was unsure when Mr Muhammad and Mr Malvo would be able to stand trial in Baton Rouge.
In Washington, DC, prosecutors have charged the pair with p>first-degree murder while armed for the shooting of Mr Pascal Charlot (72) on October 3rd. Mr Charlot was standing on a street when he was killed. The charge carries a maximum penalty of life in prison.
Washington DC and Louisiana are among several jurisdictions waiting to prosecute the men suspected in a months-long shooting spree that left 14 people dead and five others wounded.
The others are Maryland, Virginia, Washington, Alabama and Georgia.
Mr Malvo (17) is being held in the Fairfax County jail in Virginia, charged in the killing of FBI analyst Linda Franklin (47) on October 14th in Falls Church, Virginia.
Mr Muhammad, now held in Prince William County, Virginia, is charged with killing Dean Harold Meyers (53).