Updated

A lawyer for an Ohio trucker who pleaded guilty to plotting to destroy the Brooklyn Bridge has prepared a motion asking a federal judge to throw out the case on the grounds that the government illegally spied on him.

Iyman Faris' challenge is among the first to seek evidence of warrantless electronic eavesdropping by the National Security Agency, a practice that began after the terrorist attacks of Sept. 11, 2001. Government officials have reportedly credited the practice with uncovering Faris' terrorist plot and several others.

Faris' attorney David Smith said he planned to file the motion Friday in U.S. District Court in Alexandria, Va. It will argue that investigators improperly obtained evidence against Faris and that his trial lawyer was ineffective.

Faris, 36, pleaded guilty in 2003 to conspiracy and aiding and abetting terrorism, and was sentenced to 20 years in prison. He has tried to withdraw his plea, saying everything in his agreement with prosecutors was false.

According to prosecutors, Faris traveled to Pakistan and Afghanistan, carrying out low-level missions for terrorists.

Prosecutors said he investigated, but ultimately ruled out, the possibility of using a gas cutter to burn through the Brooklyn Bridge's suspension cables, and that he received attack instructions from top terrorist leader Khalid Shaikh Mohammed for what they suggested might have been a second wave of terror attacks in New York and Washington.

At his sentencing, prosecutors acknowledged that federal agents were led to Faris by a telephone call intercepted in another investigation.

Critics say the NSA tactics are unconstitutional, contending that the government must go through a secretive court set up to approve surveillance warrants in the United States during national security investigations. The Bush administration has staunchly defended the practice, saying the agency only monitors calls in which one party is outside the United States and the call is believed to be related to terrorism.

A lawyer for Ali al-Timimi, an Islamic scholar in northern Virginia convicted of exhorting followers, has said he plans to challenge his case based on NSA involvement. So has an attorney for Adham Amin Hassoun, a Lebanese-born Palestinian who worked as a computer programmer in Broward County, Fla.

Al-Timimi is serving life in prison.

Hassoun is charged along with four others with being part of a North American cell dedicated to supporting violent Muslim extremists worldwide. He is awaiting trial in Miami.

On Tuesday, a civil liberties group sued AT&T Inc. for its alleged role in helping the NSA spy on the phone calls and other communications of U.S. citizens without warrants.

The class-action lawsuit, filed in U.S. District Court in San Francisco by the Electronic Frontier Foundation, seeks an end to the surveillance program and billions of dollars in damages. AT&T has declined to comment on that case.