Portland, Ore. ? The American Civil Liberties Union and several Islamic groups filed a lawsuit Wednesday against the federal government over a section of the USA Patriot Act that lets FBI agents monitor the books people read.

The ACLU called the lawsuit the first direct challenge to the provision of the act that allows the FBI to secretly order librarians and others to disclose reading lists or other information as part of terrorism investigations.

Librarians could not tell the patrons that the library had turned over records to the government and would be legally bound to secrecy forever under the part of the law targeted in the suit.

The provision gives the federal government wide latitude to seize records, books and papers in investigations of terrorism, but the ACLU said it could also apply to innocent religious leaders, charity directors or doctors.

“It’s unnecessary, dangerous and un-American,” said David Fidanque, director of the Oregon Chapter of the ACLU.

The Justice Department defends the act as a crucial weapon in the war on terrorism. Spokeswoman Barbara Comstock said the section targeted by the lawsuit goes to great lengths to protect First Amendment rights and requires court approval to obtain records.

“The Patriot Act was a long overdue measure to close gaping holes in the government’s ability, responsibly and lawfully, to collect vital intelligence information on criminal terrorists to protect our citizens from savage attacks,” Comstock said.

The lawsuit targets section 215 in the anti-terror legislation, passed by Congress soon after the Sept. 11 attacks at the urging of the U.S. Justice Department.

It waives the usual requirement of probable cause if the investigation involves terrorism, and allows federal officials sweeping authority to search the records of people who are not suspected of any crime. The FBI must prove to a court that the records have bearing on an investigation.

The lawsuit was filed in Detroit, but includes a Portland mosque that has been at the center of a terrorist investigation.

Mosque President Alaa Abunijem said investigators have already used traditional subpoenas to gather mosque records on the suspects and their families.