Washington ? The Justice Department told a court Thursday it will seek the death penalty against Zacarias Moussaoui, the only person charged in the Sept. 11 terrorist attacks against New York and Washington.

Moussaoui deserves to die because he helped plot “the largest loss of life resulting from a criminal act in the history of the United States,” prosecutors said in a filing with the trial judge in suburban Alexandria, Va.

Moussaoui, 33, a French citizen of Moroccan descent, is charged with conspiring with Osama bin Laden, the hijackers and others to commit the Sept. 11 attacks that killed more than 3,000 people. He is scheduled for trial this fall.

Four of the six counts brought against Moussaoui carry a maximum sentence of death.

The decision came after weeks of deliberations inside the Justice Department and carries international implications, especially in Europe, where the terrorism investigation continues in several countries that oppose capital punishment.

Moussaoui’s home country, France, asked Ashcroft not to seek the death penalty and noted the French would not have to cooperate with U.S. authorities on the investigation if the death penalty was invoked.

Attorney General John Ashcroft, visiting in Miami when the court was notified, asked American allies to continue their cooperation despite their misgivings.

“We ask our counterparts in the international community to respect our sovereignty, and we respect theirs,” Ashcroft said. “To the extent that they can cooperate and help us, we welcome that cooperation.”

The decision didn’t surprise Moussaoui’s mother, who accused U.S. officials of “looking for someone’s head” in the Sept. 11 attacks.

“I was sure,” Aicha Moussaoui said in France, referring to the expectation her son would face capital punishment. “My son is a scapegoat. They can’t find the people who are truly responsible for this crime.”

Ashcroft, a longtime death penalty advocate, said the government identified several “aggravating factors” that warrant the death penalty. “Among these reasons is the impact of the crime on thousands of victims,” the attorney general said.

“We remain committed not only to carrying out justice but also to ensuring that the rights of the victims are fully protected,” he added.

The government said in its court filing that it would seek to prove that Moussaoui committed the offenses “in an especially heinous, cruel and depraved manner in that they involved torture and serious physical abuse to the victims.”

The offenses were committed “after substantial planning and premeditation to cause the death of a person and to commit an act of terrorism,” U.S. Attorney Paul J. McNulty argued in the court filing with U.S. District Judge Leonie Brinkema.

Moussaoui participated in the planning “knowing that the act created a grave risk of death to a person” and that “the crime constituted a reckless disregard for human life,” McNulty alleged.

Before his arrest, Moussaoui attended U.S. flight schools and “enjoyed the educational opportunities available in a free society, for the purpose of gaining specialized knowledge in flying an aircraft in order to kill as many American citizens as possible,” the document said.

The government also highlighted the destruction caused when two of four hijacked jetliner crashed into the World Trade Center in New York:

Â343 members of the New York City fire department died, including the majority of its upper management. It also lost 92 pieces of equipment.

Â37 Port Authority police officers and 38 Port Authority civilian authorities died;

Â23 New York City police officers perished.

Moussaoui is charged with conspiring to commit acts of terrorism, destroy aircraft, use airplanes as weapons of mass destruction and murder U.S. employees. In court papers, prosecutors accused Moussaoui of some of the same activities as the Sept. 11 hijackers by taking flight training in the United States, inquiring about crop dusting and purchasing flight-deck training videos.

Moussaoui received money in July and August from Ramzi Bin al-Shibh, an alleged member of a German terrorist cell who was a roommate of Mohammed Atta, the suspected ringleader in the attacks, the indictment said. The FBI contends Bin al-Shibh may have been planning to be the 20th hijacker.

The indictment also alleged that Moussaoui attended an al-Qaida camp in Afghanistan and by the end of September 2000 was making moves similar to some of the hijackers.

Prosecutors in northern Virginia first gave strong signals they considered this a capital case when they wrote March 7 to dozens of victims’ families to say that, pending Ashcroft’s final approval, “the United States will be asking the jury to find that defendant Moussaoui should be executed should he be found guilty.”

The top prosecutors in the case have asked the families to tell their personal stories of grief and loss since the attacks. Authorities planned to interview family members of victims April 8 in Boston, where the two planes took off that struck the World Trade Center.

Prosecutors had until Friday to file their decision to seek the death penalty. The law requires that the defense be notified in advance so lawyers can prepare properly, and Brinkema had set Friday as the deadline.