For the second time in a year, a federal judge ordered the military Wednesday to stop requiring anthrax vaccines (search) for U.S. military personnel.

In response, the Pentagon halted mandatory anthrax vaccinations "until further notice," but noted the court did not question the safety or effectiveness of the vaccine.

U.S. District Judge Emmet G. Sullivan said the Food and Drug Administration (search) violated its own procedures when it gave final approval to the vaccine last year because it failed to give the public an adequate opportunity to comment.

"The men and women of our armed forces deserve the assurance that the vaccines our government compels them to take into their bodies have been tested by the greatest scrutiny of all — public scrutiny," Sullivan said.

Justice Department spokesman Charles Miller said the government was reviewing the anthrax decision and has made no decision yet whether to appeal.

Six unidentified service members had sued the Defense Department, arguing that the vaccine is experimental and that it was being improperly used for inhalation anthrax as well as exposure of the bacteria through the skin.

"We're ecstatic," said Mark Zaid, their attorney. "It validates our position of six years that the program was illegal and ill-conceived from day one."

After the ruling, the Defense Department said the program remained "an important force protection measure" but said it would temporarily suspend it as it did last year after a similar injunction.

"DoD remains convinced that the [vaccination program] complies with all legal requirements and that anthrax vaccine is safe and effective," Secretary of Defense Donald Rumsfeld (search) wrote Wednesday in a memo to top Pentagon officials.

Sullivan first ordered a halt to the mandatory vaccinations on Dec. 22, saying that vaccine was being used for an unapproved purpose. Eight days later, the FDA issued an order intended to give the vaccine final approval for use to prevent inhaled anthrax. Sullivan later lifted the ban, except for the six plaintiffs.

The soldiers had asked Sullivan to reinstate the prohibition. He agreed, rejecting the government's claim that the FDA had considered arguments against the vaccine.

"While some individuals may have submitted comments as part of a citizen petition, it is clear to this court that if the status of the anthrax vaccine were open for public comment today, the agency would receive a deluge of comments and analysis that might inform an open-minded agency," he said.

Without the FDA's final approval, the vaccine is considered investigational. Congress has prohibited the military from giving investigational drugs to soldiers without their consent unless there is a presidential waiver.

More than 900,000 servicemen and women have received the shots, among the millions of doses of various vaccines administered to troops. Hundreds of service members have been punished or discharged for refusing them, according to the Pentagon.