Arizona shooting suspect charged with trying to assassinate Rep. Giffords

Federal authorities on Sunday charged Jared Lee Loughner with the attempted assassination of Rep. Gabrielle Giffords (D) of Arizona as well as the murders of the chief federal judge in the state and an aide to Ms. Giffords.

Giffords, who remains in critical condition, was shot Saturday morning outside a Safeway in Tucson, where she was holding a "Congress on Your Corner" event to meet with constituents. Six people were killed by the gunman and 13 others wounded.

Mr. Loughner, 22, who was apprehended at the scene after being overpowered by people in the crowd around Giffords, likely will also face state charges. Other federal charges against Loughner include the attempted murder of two additional members of Giffords’ staff.

President Obama, who earlier described the shooting as "an unspeakable tragedy," called Sunday for Americans to observe a moment of silence Monday at 11 a.m. (eastern standard time) to honor the slain victims as well as those still fighting to live.

“It will be a time for us to come together as a nation in prayer or reflection, keeping the victims and their families closely at heart,” the president said in a statement. He signed a proclamation Sunday calling for flags to be flown at half-staff.

Court documents filed Sunday in the US District Court in Phoenix suggest that the violent attack was a premeditated assassination attempt. Federal investigators executing a search warrant on Loughner’s home opened a safe and discovered an envelope with handwriting stating “I planned ahead,” and “My assassination,” and the name “Giffords,” according to court documents. The envelope includes what agents said appears to be Loughner’s signature.

FBI Director Robert Mueller, who flew to Arizona after the shooting, said at a news conference Sunday in Tucson before the federal charges were announced that Loughner was not cooperating with the investigation but is believed to have acted alone. It was premature to speculate on a motive, Mr. Mueller said, but it "appears that the target was the congresswoman.”

Investigators had sought a second man, described as a "person of interest," for questioning, but Sunday night the Tucson Sheriff's Department said the man had been cleared. The man, who was seen in video surveillance tapes, is a cab driver who reportedly told detectives that he drove Loughner to the strip mall at 9:59 a.m. and had briefly followed Loughner while he sought change to pay his fare. Detectives are satisfied with the explanation, the Sheriff's Department said.

Giffords was shot in the head at close range, Pima County Sheriff Clarence Dupnik said. Doctors treating Giffords at University Medical Center described her condition Sunday morning as critical, but said she has responded to simple commands. Doctors say they remain cautiously optimistic about her prognosis. She remains on a ventilator.

In all, 20 people were shot. The six killed are: US district Judge John Roll, 63, who stopped by the event to say hello to Giffords. He had been the chief judge for the District of Arizona since 2006 and a federal judge since 1991; Gabriel Zimmerman, 30, one of Giffords’s aides; Dorwin Stoddard, 76, a retired construction worker; Christina Greene, a 9-year-old who wanted to meet Giffords; Phyllis Schneck, 79, and Dorothy Morris, 76.

The death toll might have been greater had bystanders not subdued the gunman and held him until authorities arrived at the scene, Sheriff Dupnik said.

The first to react was a woman identified as Patricia Maisch, who was there to get her picture taken with Giffords, the sheriff's department said. She rushed the gunman as he attempted to reload his semiautomatic weapon and her intervention allowed Roger Salzgeber and Bill Badger to tackle the gunman to the ground, and along with Joseph Zamudio, they restrained him for authorities.

Loughner, who has been characterized as “disturbed,” reportedly has attended similar events in the past, Dupnik said. According to the federal court documents, investigators also recovered from the suspect's safe an Aug. 30, 2007 letter to Loughner from Giffords’ office, thanking him for attending one of her public meetings at a Tucson shopping mall.

Public records show he has had minor run-ins with the law. He also has posted various ramblings on social media sites.

Although the Tucson office of Gifford – who was reelected in November in a tight, hotly contested campaign – was vandalized last year, Dupnik said there was no security with her at the Saturday event.

Unless a known threat exists against an elected official, no security detail is provided if it isn’t specifically requested, the sheriff said.

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Investigators also have determined that Judge Roll, who had stopped at the event to say hello to his friend Giffords, was not targeted and his killing was “a fluke,” said David Gonzales, US Marshall for Arizona.

“There were no threats that were out there,” Mr. Gonzales said.

The four-page affidavit filed in support of the federal charges does not shed more light on why, specifically, Loughner chose Giffords as a target. It is unclear whether other evidence was seized at Loughner’s home that has not been made public.

The affidavit also reveals that Loughner, who has been described as a college drop out with mental problems, purchased the murder weapon – a 9 millimeter Glock – on Nov. 30, 2010 at Sportman’s Warehouse in Tucson.

The federal charges will likely be amended. Because authorities chose to proceed first in federal court, the charges are linked to the federal crimes of attempting to kill a member of Congress, unlawfully killing federal officials, and unlawfully attempting to kill federal officials.

Murder and other charges may also be prosecuted in state court in Arizona.

Tucsonans are still reeling from the shock of the shootings. Arizonans have held various vigils for the victims.

“This is something that you read about happening somewhere else, not here,” said Isabel De La Torre, who works in a clothing store near the scene of the shooting.

Added her colleague, Kaye Frey: “This is just terrible. It is so sad.”

Loughner will make an initial court appearance at 3 p.m. Monday before Magistrate Judge Lawrence Anderson at the Sandra Day O'Connor Courthouse in Phoenix.

Staff writer Warren Richey contributed to this report.