Updated

Beltway Sniper suspects John Muhammad and John Lee Malvo will be charged with six counts of first-degree murder in Maryland, prosecutors said Friday.

State's Attorney Douglas Gansler said he will seek the death penalty for the 41-year-old Muhammad if he is convicted.

But Maryland prosecutors will not seek the death penalty against Muhammad's 17-year-old sidekick, Malvo, because of his age -- although they plan to try him as an adult.

"Obviously we have different views in Maryland and Virginia on whether to apply the death penalty to a juvenile," Gansler said. "We don't feel the death penalty is appropriate for juveniles."

Virginia will have the opportunity to try Malvo -- and seek a death sentence -- after he is tried in Maryland. He and Muhammad are accused of killing 10 people -- six in Maryland, three in Virginia and one in Washington, D.C., during a three-week murder spree. Three other people were wounded, two critically.

A material witness warrant was issued for a New Jersey man who co-owned a car with Muhammad that authorities say was used in the sniper shootings. Authorities have not been able to find Nathanel O. Osbourne, 26, FBI spokeswoman Linda Vizi said in Philadelphia.

The FBI stressed that Osbourne was not a subject of the investigation in the sniper shootings. A federal judge sealed the documents pertaining to the warrant, Vizi said.

Gansler announced the murder charges after a meeting with prosecutors from jurisdictions where the killings took place. He said each of the jurisdictions has a vital interest in the case, but Montgomery County was the "community most affected and most impacted by the shootings." Six of the slayings took place in Maryland.

"As a group, the prosecutors involved in the investigation remain united in the cause to ensure that justice is served, that these men are held accountable for the acts they allegedly committed," Gansler said.

Muhammad and Malvo also were charged with capital murder in Montgomery, Ala., Friday, in the fatal shooting of a woman during a robbery there last month. The chief of police there said authorities would seek the death penalty for both suspects.

The two were charged in Alabama with one count each of capital murder and one count of attempted murder in the Sept. 21 robbery that killed a woman and wounded another outside a liquor store in Montgomery.

"We want to send a very strong message to not only this community and this state but the country that this is not the kind of conduct, this is not what we expect of civilized society," Police Chief John Wilson said. "We're going to make an example of somebody."

Investigators in the Washington area said a rifle found in the suspects' car has been linked to 11 of the shootings.

"I think the general consensus is that the case will be tried first in Montgomery County," Gansler, the county's top prosecutor, said before meeting with his counterparts Friday. "We have the best evidence in the case. Also, the investigation was run out of Montgomery County."

Virginia and Alabama are more likely to actually carry out executions than the other jurisdictions involved in the case.

In Virginia, Prince William County Commonwealth's Attorney Paul Ebert said he wants to seek the death penalty for an Oct. 9 killing by the sniper.

Virginia Gov. Mark R. Warner said the death penalty is "clearly" appropriate, but noted there could be a series of prosecutions involving several jurisdictions.

Virginia has executed 86 people since capital punishment was reinstated in the United States in 1976 -- more than any state but Texas. In the same period, Alabama has executed 23. Maryland has put just three people to death, and all executions have been suspended under a moratorium imposed in May by Gov. Parris Glendening.

Glendening and other state officials said Friday they expect the moratorium would be lifted by the time the sniper case is concluded.

The states' laws also differ in the criteria for execution. A 17-year-old would be eligible for the death penalty in Virginia and Alabama but not in Maryland.

Maryland allows the death penalty for multiple murders arising out of the same incident. But the question is whether the sniper killings constitute the same incident.

Virginia has more avenues than Maryland for seeking the death penalty, including a new post-Sept. 11 provision that allows for execution when the killer has "intent to intimidate the civilian population at large."

The U.S. attorney in Baltimore, Thomas DiBiagio, has declined to comment on the possibility of federal prosecution.

Federal prosecutors -- because of uncertainty about whether the federal death penalty would apply in this case -- would probably defer to their local counterparts, said Robert Cleary, a former prosecutor who led the government's case against Theodore Kaczynski, the Unabomber.

"The neatest and cleanest way to prosecute this is with state murder charges," Cleary said. "I think you're going to see the locals prosecute."

The Associated Press contributed to this report.