Foreigners who act as informants in the war against terror could be put on a fast track to American citizenship under a program announced Thursday.

Attorney General John Ashcroft said the "responsible cooperators program," which goes into effect immediately, would give illegal aliens who qualify the chance to stay in the country, and allow those abroad with visa problems to enter the country.

Ashcroft said "non-citizens who help us apprehend terrorists or stop terrorist attacks" will be given assistance in getting work authorizations, permanent residence permits, and applications for citizenship.

"People who have information about terrorist activity must make a choice. Either they will come forward to save American lives or they will remain silent against evil. The people who have the courage to make the right choice deserve to be welcomed as guests in our country and perhaps one day to become fellow citizens," Ashcroft told reporters during a conference to announce a law enforcement search for an escaped fugitive wanted for sending anthrax letter hoaxes to women's health clinics.

Any individual in any country regardless of their immigration or legal status would be able to participate in the program, Ashcroft said.

Aliens who participated in terrorist acts would not be eligible for the program. The Justice Department's criminal division will approve each of the participants in order to prevent people who have already committed terrorist attacks from taking advantage of the system.

The INS currently has a program called the "S-visa", which requires informants to have critical and reliable information on terrorist acts, and also requires them to prove their lives are endangered by providing this information. The new program does not require informants to prove their lives are in danger.

The INS is only allowed to grant 50 S-visas a year, but the new program allows for an unlimited number of participants.

Ashcroft added that embassy officials can not inquire about the status of individuals bringing information to them, only inquire about the information and evaluate its import.

"That evaluation will be the basis on which the individual will receive the benefit that will flow from the receipt of useful and reliable information," he said.  The information they are looking for would enable law enforcement to detect and prevent terrorist activities or to convict individuals responsible for terror. 

The information can also be stand-alone material, "the missing link in a chain of evidence," Ashcroft said.

Earlier in the day, Ashcroft defended the use of military tribunals to prosecute foreigners who are implicated in terror plots, a tactic in the war against terror that some in Congress say the president does not have the authority to use.

"Can you imagine a highly publicized trial where we'd be asked to reveal intelligence sources? Can you imagine a terrorist on trial and using it as a propaganda tool? Can you imagine the focus of really identifying a courthouse in a community where the trial was being held as a focus for terrorists? We're not going to do that," Ashcroft said.

White House spokesman Ari Fleischer asserted Thursday that Bush does have the authority to use military courts, because such tribunals have been upheld by the Supreme Court and "are a part of the law." He also said Bush has no quarrel with Congress for convening hearings on the matter.

"It is the mission of Congress to look carefully at any action the administration takes," Fleischer said. "The president is confident that if his actions were ever put to a vote, it would find widespread bipartisan support in the Congress ... including the military tribunals."

Fox News' Bryan Sierra and the Associated Press contributed to this report.