Dr. George Tiller, one of the nation's few providers of late-term abortions despite decades of protests and attacks, was shot and killed Sunday in a church where he was serving as an usher. The gunman fled, but a 51-year-old suspect was detained some 170 miles away in suburban Kansas City three hours after the shooting, Wichita Deputy Police Chief Tom Stolz said. Although Stolz refused to release the man's name, Johnson County sheriff's spokesman Tom Erickson identified the detained man as Scott Roeder. A 51-year-old man named Scott Roeder was booked into the Sedgwick County Jail in Wichita on Sunday night on one count of first-degree murder and two counts of aggravated assault. He was being held without bond. Court records and Internet postings show that someone using the name Scott Roeder has a criminal past and has expressed anti-abortion opinions on sympathetic Web sites. Long a focus of national anti-abortion groups, including a summer-long protest in 1991, Tiller was shot in the foyer of Reformation Lutheran Church. Tiller's attorney, Dan Monnat, said Tiller's wife, Jeanne, was in the choir at the time. The slaying of the 67-year-old doctor is "an unspeakable tragedy," his widow, four children and 10 grandchildren said in statement. "This is particularly heart-wrenching because George was shot down in his house of worship, a place of peace." The family said its loss "is also a loss for the city of Wichita and women across America. George dedicated his life to providing women with high-quality health care despite frequent threats and violence." Stolz said all indications were that the gunman acted alone, although authorities were investigating whether he had any connection to anti-abortion groups. Tiller's Women's Health Care Services clinic is one of just three in the nation where abortions are performed after the 21st week of pregnancy. The clinic was heavily fortified and Tiller often traveled with a bodyguard, but Stolz said there was no indication of security at the church Sunday. Anti-abortion groups denounced the shooting and stressed that they support only nonviolent protest. The movement's leaders fear the killing could create a backlash just as they are scrutinizing U.S. Supreme Court nominee Sonia Sotomayor, whose views on abortion rights are not publicly known. "We are shocked at this morning's disturbing news that Mr. Tiller was gunned down," Troy Newman, Operation Rescue's president, said in a statement. "Operation Rescue has worked for years through peaceful, legal means, and through the proper channels to see him brought to justice. We denounce vigilantism and the cowardly act that took place this morning." But Randall Terry, a veteran anti-abortion activist who founded Operation Rescue and whose protests have often targeted Tiller, called the slain doctor "a mass murderer," adding: "He was an evil man - his hands were covered with blood." At Tiller's church, Adam Watkins, 20, said he was sitting in the middle of the congregation when he heard a small pop at the start of the service. "We just thought a child had come in with a balloon and it had popped, had gone up and hit the ceiling and popped," Watkins said. Another usher came in and told the congregation to remain seated, then escorted Tiller's wife out. "When she got to the back doors, we heard her scream, and so we knew something bad had happened," Watkins said. President Barack Obama said he was "shocked and outraged" by the murder. "However profound our differences as Americans over difficult issues such as abortion, they cannot be resolved by heinous acts of violence," he said. Reformation Lutheran Church held a special service Sunday evening. Dr. Michael Bates, who has known Tiller for more than 25 years, described it as a simple service featuring Bible readings. Reporters were kept out. At a vigil in downtown Wichita that attracted a few hundred people, about 10 protesters from Topeka's Westboro Baptist Church held signs emblazoned with such messages as "Abortion is bloody murder" and "Baby killer in hell." The church is known for picketing military funerals. The protesters and about 20 Tiller supporters shouted at each other while police watched over them nearby. Tiller had endured threats and violence in the past. A protester shot Tiller in both arms in 1993, and his clinic was bombed in 1985. More recently, Monnat said Tiller had asked federal prosecutors to step up investigations of vandalism and other threats against the clinic out of fear that the incidents were increasing and that Tiller's safety was in jeopardy. Stolz, however, said police knew of no threats connected to the shooting. In early May, Tiller had asked the FBI to investigate vandalism at his clinic, including cut wires to surveillance cameras and damage to the roof that sent rainwater pouring into the building. In 1991, the Summer of Mercy protests organized by Operation Rescue drew thousands of anti-abortion activists to this city for demonstrations marked by civil disobedience and mass arrests. Tiller began providing abortion services in 1973. He acknowledged abortion was as socially divisive as slavery or prohibition but said the issue was about giving women a choice when dealing with technology that can diagnose severe fetal abnormalities before a baby is born. Nancy Keenan, president of abortion-rights group NARAL Pro-Choice America, issued a statement praising Tiller's commitment. "Dr. Tiller's murder will send a chill down the spines of the brave and courageous providers and other professionals who are part of reproductive-health centers that serve women across this country. We want them to know that they have our support as they move forward in providing these essential services in the aftermath of the shocking news from Wichita," Keenan said. The doctor's violent death was the latest in a string of shootings and bombings over two decades directed against abortion clinics, doctors and staff. The last killing of an abortion doctor was in October 1998 when Dr. Barnett Slepian was fatally shot in his home in a suburb of Buffalo, N.Y. A militant abortion opponent was convicted of the murder. Federal marshals protected Tiller during the 1991 Summer of Mercy protests, and he was protected again between 1994 and 1998 after another abortion provider was assassinated and federal authorities reported finding Tiller's name on an assassination list. Someone named Scott Roeder, then 38, was charged in Topeka, Kan., in 1996 with criminal use of explosives for having bomb components in his car trunk and sentenced to 24 months of probation. However, his conviction was overturned on appeal the next year after a higher court said evidence against Roeder was seized by law enforcement officers during an illegal search of his car. At the time, police said the FBI had identified Roeder as a member of the anti-government Freemen group, an organization that kept the FBI at bay in Jordan, Mont., for almost three months in 1995-96. Someone posting to the Web site of Operation Rescue in May 2007 used the name "Scott Roeder" in response to a scheduled vigil to "pray for an end to George R. Tiller's late-term abortion business." "Bleass everyone for attending and praying in May to bring justice to Tiller and the closing of his death camp," the posting read. "Sometime soon, would it be feasible to organize as many people as possible to attend Tillers church (inside, not just outside) to have much more of a presence and possibly ask questions of the Pastor, Deacons, Elders and members while there? Doesn't seem like it would hurt anything but bring more attention to Tiller."