(CN) - Conservative activist James O'Keefe, who entered ACORN offices dressed as a pimp on hidden camera, is one of four men facing criminal charges for allegedly trying to break into Democratic Sen. Mary Landrieu's office while posing as telephone repairmen, the FBI announced Tuesday.
O'Keefe, along with 24-year-olds Joseph Basel, Robert Flanagan and Stan Dai, entered the Federal Building and tried to interfere with Sen. Landrieu's phone line, the FBI said in a statement.
The men allegedly dressed in work clothes, including hard hats and tool belts, and told a member of the Louisiana senator's staff that they were from the phone company and needed to repair the main phone system. They claimed to have left their credentials in the vehicle, according to the FBI.
They were soon apprehended by U.S. marshals.
"This is a very unusual situation and somewhat unsettling for me and my staff," Landrieu said in statement Tuesday night. She said she was interested in finding out what motivated O'Keefe and the others.
O'Keefe, 25, is a video-journalist and self-described "progressive radical" who champions conservative causes.
He gained media attention last year by filming community organizers from ACORN answering his bogus inquiries. Among other ruses, he pretended to be a child trafficker and a pimp interested in turning a home into a brothel.
O'Keefe released the videos on his Web site BigGovernment.com, which soon became YouTube sensations.
In a previous stunt, O'Keefe recorded Planned Parenthood employees who appeared to accept a large donation earmarked for aborting black fetuses.
In a statement, an ACORN spokesperson said O'Keefe's arrest was "further evidence of his disregard for the law in pursuit of his extremist agenda."
O'Keefe faces a lawsuit in Baltimore for videotaping ACORN employees last summer, and the Philadelphia branch sued O'Keefe in federal court this month on emotional distress claims.
The four men are charged with entering federal property under false pretenses for the purpose of committing a felony. If convicted, they face up to 10 years in prison and a $250,000 fine.
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