At a news conference Sunday in Tucson, FBI Director Robert Mueller said it was premature to say what motivated the shooting of Giffords. BENJIE SANDERS / ARIZONA DAILY STAR

FBI agents who searched the home of mass-shooting suspect Jared Lee Loughner found evidence that U.S. Rep. Gabrielle Giffords was the target of a planned assassination attempt.

Special agents searched Loughner's Tucson home in the 7700 block of North Soledad Avenue, near North Thornydale and West Magee roads, Saturday afternoon.

Kept inside a safe in the home was an envelope with writing on the outside.

"I planned ahead," "My assassination" and the name Giffords appear on the envelope, along with what appears to be Loughner's signature, FBI Special Agent Tony M. Taylor said in court documents filed Sunday.

Also found in the safe was a letter from Giffords thanking Loughner for attending an August 2007 "Congress on Your Corner" event at the Foothills Mall.

At that event, Giffords took a question from Loughner. According to two of his high school friends, the question was essentially this: "What is government if words have no meaning?"

Loughner was angry about her response - she read the question and had nothing to say, the friends told The Associated Press on Sunday.

"He did not like government officials, how they spoke. Like they were just trying to cover up some conspiracy," one friend said.

On Saturday, Giffords held her 20th "Congress on Your Corner" event since taking office, this one at a Safeway at North Ina and West Oracle roads.

There, Loughner, 22, is accused of opening fire with a Glock 9 mm semiautomatic weapon, killing six people - including a federal judge and a child - while wounding Giffords and 13 others. The judge, John M. Roll, was there to thank Giffords for helping his efforts to help an overburdened federal court system, court documents now say.

The total number of victims was upped to 20 from 19 at a news conference Sunday held by Pima County Sheriff Clarence Dupnik and FBI Director Robert Mueller.

Mueller flew into Tucson at President Obama's behest to oversee the investigation of what he called "an attack not only on dedicated public servants, but on a 9-year-old girl" and many others.

Court date set for Today

A formal complaint lodged Sunday in federal court in Phoenix charges Loughner with killing U.S. District Court Chief Judge Roll, 63, and Gabriel Zimmerman, 30, a Giffords staff member.

Loughner also is charged with attempting to murder Giffords and two other members of her staff, Pamela Simon and Ron Barber. Giffords was shot in the head and is in critical condition. Simon and Barber are recovering from their wounds, doctors say.

Loughner is scheduled to make his initial court appearance at 3 p.m. today before Magistrate Judge Lawrence Anderson at the Sandra Day O'Connor Courthouse in Phoenix. He remains in federal custody.

The U.S. has charged Loughner only in regard to the victims who worked for the federal government: the judge, the Congress member and her staff.

Loughner will face state charges in regard to those victims who were not named in the federal complaint, said Pima County Attorney Barbara LaWall.

The federal government has no jurisdiction over their cases.

The other people slain Saturday at the event were Christina-Taylor Green, 9, a student-government leader who wanted to meet Giffords; Dorwan Stoddard, 76; Phyllis Schneck, 79; and Dorothy Morris, 76.

"If ever there was a capital case, this might well be it," LaWall said, adding that it will undergo the same scrutiny as other potential death-penalty cases.

Faulty magazine

Also on Sunday, more gripping details of the heroic actions of Tucsonans caught up in the shooting rampage were revealed by the Sheriff's Department.

After Loughner emptied the magazine of his 9 mm Glock - which he bought legally in November from a Tucson gun store - he reloaded, officials said.

But local resident Patricia Maisch grabbed the magazine, sheriff's Bureau Chief Richard Kastigar said.

Roger Salzgeber, who was waiting in line with his wife to see Giffords, and Bill D. Badger tackled Loughner. Shopper Joseph Zamudio helped restrain the suspect, sheriff's officials said.

It turns out the magazine was faulty, but obviously Maisch couldn't have known that, Kastigar said.

Because of the citizens' heroic actions, a "greater catastrophe" was averted, Sheriff Dupnik said.

Although Dupnik initially reported Maisch had been shot, she was not injured.

Authorities working hard

FBI Director Mueller said authorities continue to work around the clock to determine why Loughner committed such "heinous" acts.

Asked if Loughner had a documented history of mental health issues, Dupnik said he did not know.

Mueller said he was not discounting the possibility of charging Loughner with crimes under domestic-terrorism statutes, but he said it was "premature to say what the motivations were or to draw generalizations."

A suspicious package found at Giffords' office after the shootings did not contain any explosive materials, but investigators are looking into who sent the package and why, Mueller said. FBI lab analysts will try to obtain DNA and fingerprints from the package, he said.

Taxi driver cleared

Also on Sunday, Kastigar announced that detectives interviewed the "person of interest" they initially thought might have been an accomplice in the shootings and cleared him of any wrongdoing.

The man, a cabdriver, told detectives that he gave Loughner a ride to the Safeway and they entered the store together so Loughner could obtain change to pay his fare, Kastigar said. Records substantiate the driver dropped Loughner off at 9:59 a.m., he said.

The first report of a shooting came at 10:11 a.m., and a deputy and paramedics were at the scene by 10:16 a.m., he said.

"If ever there was a capital case, this might well be it."

Barbara LaWall, Pima County attorney

Contact reporter Kim Smith at or 573-4241.