WASHINGTON -- More than 700 people were arrested on immigration violations and thousands more subjected to FBI interviews in an intense government effort to avert a terrorist attack aimed at disrupting the election.
As with past unrealized Al Qaeda threats, law enforcement officials said yesterday they do not know for sure whether any of those arrests or interviews foiled an attack.
"It's very hard to prove a negative," Michael Garcia, chief of Immigration and Customs Enforcement, said in an interview yesterday. "We did cases and operations for people we thought posed national security concerns. We didn't arrest anyone who had a bomb."