The FBI is cautioning local authorities the Al Qaeda (search) terror network may be recruiting non-Arabs less likely to attract notice as they carry out attacks in the United States.

Al-Qaida especially wants operatives who have American citizenship or legal residency status, the FBI's counterterrorism division said in its weekly bulletin to 18,000 law enforcement agencies nationwide.

"Finding operatives with U.S. status would greatly facilitate Al Qaeda's ability to carry out an attack within the United States," said the bulletin, obtained Friday by The Associated Press.

The new warning comes amid a continuous stream of intelligence indicating that Al Qaeda is determined to strike the United States in the summer or fall. Officials have said the terror network blamed for the Sept. 11, 2001, attacks hopes to inflict mass casualties again and disrupt the political process in this presidential election year.

The FBI bulletin does not mention a possible time, place or method of attack. Security is expected to be especially tight at this summer's political conventions, which begin July 26 with the Democratic Party's gathering in Boston. The Republican convention (search) is Aug. 30-Sept 2 in New York.

Using non-Arabs might make it easier for Al Qaeda to circumvent security measures in Europe and the United States, the bulletin said. Of special concern are people with ties to Islamic extremist groups in North Africa and parts of Asia outside the Middle East.

Still, the FBI said, almost all Al Qaeda operatives in the past have traveled at least once to South Asia, particularly Afghanistan and Pakistan, for "consultation and training."

Afghanistan was the site of Al Qaeda terror training camps before the U.S. invasion of that country in 2001 and al-Qaida leader Osama bin Laden (search) is believed to be hiding out in remote regions of Pakistan, where the terror network has many sympathizers.

Because of its hardline Muslim views, Al Qaeda favors using male operatives between the ages of 18 and 35 in its attacks, the FBI said. But women could also be recruited, especially from areas considered more liberal on the subject such as North and East Africa and the eastern Mediterranean, the FBI notice said.

Despite its warning about non-Middle Easterners, the bulletin said police and security personnel should not discount the possibility that Arabs could still be used in a U.S. attack, particularly if they are already in the United States.