PHOENIX -- The 22-year-old loner accused of trying to assassinate a U.S. congresswoman and killing six others, appeared in court Monday, his head shaved, a cut on his right temple and in handcuffs. He stared vacantly at a packed courtroom and sat down to listen to whispered instructions from his attorney.
Rep. Gabrielle Giffords lay about a 100 miles (160 kilometers) away in an intensive care unit, gravely wounded after being shot through the head but able to give a thumbs-up sign that doctors found as a reason to hope. Thirteen other people were injured in the bursts of gunfire outside an Arizona supermarket.
The shootings, which claimed the lives six people, including of a federal judge, a congressional aid and a nine-year-old girl, have dominated news in the U.S., prompting outrage and sparking debate over gun control and whether heated political rhetoric fueled the incident.
Before the hearing began, Jared Loughner's court-appointed attorney Judy Clarke whispered to the defendant, who only spoke to say "yes," when the judge asked if he understood that he could face life in prison -- or the death penalty for the killings.
Clarke, had earlier defended "Unabomber" Ted Kaczynski and Al-Qaida operative Zacarias Moussaoui among others.
The judge ordered Loughner held without bail.
A Mass for all the victims was scheduled Tuesday at St. Odelia's Parish in Tucson.
Among the dead was 9-year-old Christina Taylor Green, who was born on the day of the Sept. 11, 2001, terrorist attacks. Her funeral is Thursday.
It was unclear when funerals will be held for the other victims, including one of Giffords' aides.
President Barack Obama will travel to Arizona on Wednesday to attend a memorial service for the victims, a senior administration official told The Associated Press. The official spoke on the condition of anonymity because the president's trip had not been publicly announced.
Earlier Monday, Americans observed a moment of silence for the victims of the rampage, from the South Lawn of the White House and the steps of the U.S. Capitol to legislature beyond Arizona and the International Space Station.
There, Giffords' brother-in-law, Scott, the commanding officer, spoke over the radio. Flight controllers in Houston fell silent.
"As I look out the window, I see a very beautiful planet that seems very inviting and peaceful," he said. "Unfortunately, it is not."
"These days, we are constantly reminded of the unspeakable acts of violence and damage we can inflict upon one another, not just with our actions, but also with our irresponsible words," he said.
"We're better than this," he said. "We must do better."
On a frigid morning outside the White House, Obama and first lady Michelle Obama stood side by side, each with their hands clasped, heads bowed and eyes closed.
On the steps of the U.S. Capitol, congressional staff and other employees did the same.
At the Supreme Court, the justices paused for a moment of silence between the two cases they were hearing Monday morning. Arizona's chief federal judge, John Roll, was killed in the attack.
The president called for the country to come together in prayer or reflection for those killed and those fighting to recover.
"In the coming days we're going to have a lot of time to reflect," he said. "Right now the main thing we're doing is to offer our thoughts and prayers to those who've been impacted, making sure we're joining together and pulling together as a country."
The shooting highlighted tensions that have been running high between conservatives and liberals in the United States, where activists and talk show radio hosts have been employing increasingly violent language in their criticisms of the Obama administration.
In 2009, a protestor was discovered carrying a gun at another Giffords rally and there were signs the congresswoman was becoming concerned about the strident tone of the political debate in the U.S.
The day before Giffords was wounded, she sent an e-mail to a friend discussing how to "tone our rhetoric and partisanship down."
In the message, obtained by The Associated Press, the Democratic congresswoman wrote to Republican Kentucky Secretary of State Trey Grayson to congratulate him on his new positions at Harvard University.
"After you get settled, I would love to talk about what we can do to promote centrism and moderation. I am one of only 12 Dems left in a GOP district (the only woman) and think that we need to figure out how to tone our rhetoric and partisanship down." GOP stands for Grand Old Party and refers to the Republicans.
Giffords, narrowly managed reelection in 2010, in Arizona a conservative state known for its liberal gun control laws and which made headlines last year after it passed a draconian anti-immigration law allowing police to stop those they suspected of being in the country illegally.
Giffords was a vocal opponent of the law and a supporter of Obama's healthcare law widely opposed by conservatives.
In total, 20 people were shot in the rampage outside a supermarket where Giffords held her meeting. Giffords was shot in the head, and remains in intensive care.
Among the six people killed were a 9-year-old girl who was born on the day of the Sept. 11, 2001 terrorist attacks and was interested in public service, as well as one of Giffords' aides.
Loughner is charged with one count of attempted assassination of a member of Congress, two counts of killing an employee of the federal government and two counts of attempting to kill a federal employee. Those are federal charges.
State prosecutors, meanwhile, are researching whether they have to wait until after the federal case is resolved, or if they can proceed with local charges at the same time, an official said.
Giffords, 40, was shot in the head, at close range. She was in critical condition at Tucson's University Medical Center. Two patients were discharged Sunday night. Seven others, remained hospitalized.
Recent CT scans showed no further swelling in the brain, but doctors were guarded.
"We're not out of the woods yet," her neurosurgeon Dr. Michael Lemole said. "That swelling can sometimes take three days or five days to maximize. But every day that goes by and we don't see an increase, we're slightly more optimistic."
Her doctors have declined to speculate on what specific disabilities Giffords may face.
With few new details emerging at the hearing, questions remained about what could have motivated someone to arm himself with a pistol and magazines carrying 33 bullets each, and raining gunfire on a supermarket parking lot crowded with men, women and children.
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