Agents with US Immigration and Customs Enforcement, a Homeland Security Department component known as ICE, are matching identities of visa violators nationwide with names on secret government terrorism databases in hopes of finding al-Qaeda operatives. "We're intensifying it in the days leading up to the election," ICE spokesman Dean Boyd said Friday.

Some groups representing Muslims and Arab-Americans are concerned some people may be targeted because of their ethnicity or religious beliefs.

"If somebody breaks the law in terms of their immigration status, they should pay the price," said Ibrahim Hooper, spokesman for the Council on American-Islamic Relations. "We can only hope they are not targeting people based on whether they are Muslim." Since its inception in June 2003, ICE's Compliance Enforcement Unit has opened more than 5,200 investigations of visa violators nationwide. Of those apprehended, 359 are considered "priority arrests" those with possible links to terrorism or known criminal histories.

The stepped-up initiative is one of many government efforts given new urgency by persistent intelligence indicating al-Qaeda is determined to attack inside the United States before the Nov. 2 election.