A drifter was charged with first-degree murder over a shooting spree that killed three people and wounded nine at a family planning center in Colorado.
Robert Lewis Dear, 57, made his first court appearance via video link from the El Paso County jail in Colorado Springs, where he is being held, wearing what appeared to be a protective vest.
He stood impassive next to his attorney as the judge advised him of his rights and read the charge against him, and set another hearing in the case for December 9, when formal charges will be filed.
Several relatives of those killed or wounded in last Friday's shooting at the Planned Parenthood clinic watched the proceedings in the courtroom.
Dear faces a minimum of life in prison and a maximum sentence of the death penalty over the killings that have revived the debate in the United States over both gun control and abortion.
Investigators have yet to publicly explain Dear's motive but several US media outlets, citing law enforcement officials, reported that he mentioned "no more baby parts" when questioned.
The officials said Dear's "rantings" also included comments about politics and President Barack Obama.
Vicki Cowart, the head of Planned Parenthood of the Rocky Mountains, said in a statement that witnesses to the shooting spree had confirmed Drew "was motivated by opposition to safe and legal abortions."
"We've seen an alarming increase in hateful rhetoric and smear campaigns against abortion providers and patients over the last few months," Cowart said. "That environment breeds acts of violence."
The rampage killed a police officer, Garrett Swasey, 44, and two civilians, Jennifer Markovsky, 35, a mother of two who was at the clinic supporting a friend, and Ke'Arre Marcell Stewart, 29, an Iraq War veteran and father of two.
Several vigils were held over the weekend in Colorado Springs, the state's second-largest city and a place known for its conservative politics and fundamental religious organizations.
An exasperated Obama said "enough is enough," as he called for tighter controls on "weapons of war."
- 'Domestic terrorism' -
There were also calls for better protection for organizations that provide abortions, a procedure that remains highly divisive in the United States.
"Whipping people into a frenzy of hate and anger while providing them with easy access to firearms has proven disastrous in this country," Senate Democratic Leader Harry Reid said in a statement.
"We have a responsibility as leaders to think very hard about what we say and do in this context."
He said Democrats were working on "reasonable gun safety proposals," and urged his Republican rivals, who hold majorities in both the Senate and House of Representatives, to support these measures.
Critics, many of whom seek to outlaw abortion in the United States, have falsely accused Planned Parenthood of selling fetal organs and body parts for profit, and encouraging women to have abortions in order to expand such operations.
Planned Parenthood receives some government funding but little of that goes for abortion procedures.
"We need to call the threats of violence and the intimidation of health care providers and patients what it is -- domestic terrorism," Karen Middleton, executive director of NARAL Pro-Choice Colorado, said in a statement.
"More public officials in Colorado and across the country, not just advocacy groups and the people on the frontlines, need to take a stand opposing domestic terrorism and supporting women's health."
The shooting was the second in weeks in Colorado Springs to leave several victims.
On October 31, a man armed with a semi-automatic rifle, a revolver and a pistol gunned down a bicyclist and two women at a house for women fighting alcoholism and drug abuse.
He was killed in a shootout with police.