More than 600 arrested in attacks

"We're counting on each American to help us defend our nation in this war,'' Attorney General John Ashcroft said Monday in announcing that investigators still were seeking 229 people who were either suspects in the attacks or were believed to have information important to the case.

Authorities have arrested or detained 614 people in the terrorism probe so far, Ashcroft said.

Overseas, police in Ireland arrested three Libyans and an Algerian Tuesday on suspicion of involvement in the Sept. 11 terrorist attacks on the United States. Police said the men are suspected of having ties to Osama bin Laden's al-Qaida network.

Police spokeswoman Lynne Nolan said the four men were arrested following police raids on properties in south Dublin early Tuesday. Three are recent immigrants while the fourth is a naturalized Irish citizen, police said on condition of anonymity.

With other terrorist attacks viewed as more likely now that U.S. forces have begun bombing Afghanistan, the FBI has advised 18,000 local law enforcement agencies and 27,000 corporate security managers to be on high alert. Warnings also have been sent to telephone companies, electrical power companies, banks, oil and gas facilities, computer companies, water service providers and railroads.

Nuclear facilities are on the highest state of alert and are screening all employees and others who have access to plants.

"Our national law enforcement network ... will continue working around the clock to find the people who were involved in the attacks and to disrupt any future plans for terrorism in America,'' the attorney general said.

The FBI investigated whether the anthrax episode in Boca Raton, Fla., was a criminal act.

Bob Stevens, a photo editor at the Sun tabloid, died after apparently inhaling anthrax, and a mailroom employee in the same building, Ernesto Blanco, had anthrax bacteria in his nostrils. The deadly bacteria was found on a computer keyboard at the tabloid office where both men worked.

A state health official doubted there were innocent explanations.

"The chances are one in a billion'' that two such cases would occur, said Dr. Landis Crockett, director of disease control for the Florida Department of Health.

"There then would be another explanation, and that would be that foul play would be suspected,'' Crockett added.

FBI investigators likewise believe the anthrax found in Florida was intentionally introduced because the bacteria are so rare and the chances of two people in the same building having it are slight, but they do not have evidence yet of a crime, law enforcement officials said Tuesday.

In Virginia, lab tests for anthrax performed on a patient with connections to the Sun have thus far been negative, Dr. Thomas Ryan of Price William Hospital in Manassas, Va., said Tuesday. "I just want to allay everybody's anxiety about this case because it just doesn't seem to fit the criteria,'' he said.

On Monday, the hospital had contacted Virginia's health department with a possible anthrax diagnosis, "one of several possible diagnoses'' for the victim.

Bennet Bolton, a senior reporter for The National Enquirer, one of the tabloids housed with the Sun in the same building in Florida, described a "cryptic'' e-mail sent to the staff in late August or early September by an intern who had worked in the newsroom during the summer.

"It intrigued us that he left such a cryptic farewell,'' Bolton said. "It was rather neutral and then he said, 'I left you a surprise for you to remember me by. Ha ha, just kidding.'''

Bolton said federal investigators were told about the e-mail.

Newsweek magazine reported on its Web site that the office received a "weird love letter to Jennifer Lopez'' a week before the Sept. 11 attacks. Inside was what was described as a soapy, powdery substance and a Star of David charm. The letter was handled by both Stevens and Blanco, according to unidentified workers cited by Newsweek.

One law enforcement official, speaking on condition of anonymity, said the FBI is trying to track down the alleged Lopez letter mentioned by Newsweek but does not believe it is a likely source for the anthrax.

Stevens, the dead photo editor, lived about a mile from an air strip where flight school owner Marian Smith said suspected hijacker Mohamed Atta rented planes. Several suspected hijackers also visited a crop-dusting business in Belle Glade, 40 miles from Stevens' home in Lantana.