Attorney General John Ashcroft (search) defended FBI interviews of some political protesters around the country before last month's Democratic convention in Boston, which critics described as an intimidation tactic.

At a news conference Friday, Ashcroft said FBI agents interviewed only protesters they believed were plotting to firebomb media vehicles at the Democratic convention or might have known about such plots.

Ashcroft said suggestions that the interviews were aimed at stifling protests were an "outrageous distortion."

"We interviewed a very limited number of people that we believed knew something about that plan," Ashcroft said.

Three Democratic lawmakers on the House Judiciary Committee (search) have criticized the FBI's interviews. They asked the Justice Department's inspector general to investigate what they called "possible violations of First Amendment (search) free speech and assembly rights."

The committee's ranking Democrat, Michigan's John Conyers, along with Reps. Robert C. "Bobby" Scott of Virginia and Jerrold Nadler of New York, said in a letter that the FBI "appears to be engaged in systematic political harassment and intimidation of legitimate anti-war protesters."

The warning of a possible attack against media trucks, disclosed days before the Democratic convention, was based on claims by an informant who described an alleged plot by self-described anarchists in the Midwest to throw Molotov cocktails at television vans, a senior U.S. law enforcement official told The Associated Press earlier this week.

Mark Silverstein, the Colorado legal director for the American Civil Liberties Union (search), has said he was "very skeptical" of the Justice Department's explanation. The ACLU, which was contacted by some of the protesters who were interviewed by the FBI, said agents never asked directly about such an alleged plot.

Gary Bald, assistant director of the FBI's counterterrorism division, said the bureau anticipates violent protests at the upcoming Republican National Convention in New York but does not have enough evidence to move against any group or person.

Federal investigators have infiltrated some organizations and are monitoring protest plans being published on the Internet.

New York officials have said they expect hundreds of thousands of people to stage demonstrations around the convention, which begins Aug. 30.