The FBI believes extremist groups continue to have members in the United States who could be called upon for terrorist attacks, the Justice Department has told the Senate Intelligence Committee.
At least one group, Hezbollah, may be more interested in using its U.S. members to raise money than to undertake attacks, the department said.
The comments, in a document released Thursday, were part of the department's written responses submitted on July 26 to questions from the committee in February.
Responding to a question about the involvement of Hezbollah, Hamas and other terrorist groups in the United States, the department said FBI investigations "indicate the continued presence of suspected extremists of various groups who could be called upon to attack in the United States."
It said Hezbollah, in particular, appears to have the ability to strike in the United States. Some Hezbollah members may have been instructed to evaluate potential targets. But that may have only been a test to prove their loyalty to Hezbollah and Iran, which backs the group.
The department noted Hezbollah has never conducted a terrorist strike in the United States. Hezbollah is blamed, though, for the 1983 bombing of a Marine Corps barracks in Beirut, Lebanon, that killed 241 American servicemen.
Hezbollah members are used mostly to raise money for the group's overseas operations, the report said. Hezbollah fighters in southern Lebanon frequently attack Israel.
"To date, it is believed that this extensive fund-raising activity itself acts as a disincentive for operational terrorist activity in the United States," according to the document.
It did not say if this was also true of other groups, such as Hamas, the militant Palestinian organization. The State Department has classified both Hezbollah and Hamas as terrorist groups.
The document also warned that the potential for terrorist attacks in the United States continues. CIA Director George Tenet and homeland security director Tom Ridge have issued similar warnings in recent weeks.
But the document also reports advances in the campaign against Usama bin Laden's Al Qaeda network, partly as a result of strong cooperation with foreign law enforcement and intelligence agencies.