A year after 10 of their female classmates were shot, some boys who escaped unharmed from West Nickel Mines Amish School are tormented by guilt, according to the author of a new book about the massacre.

Four of the five surviving girls have long since returned to classes in a new schoolhouse, but the community is also concerned about the lingering effects on the boys, Elizabethtown College professor Donald B. Kraybill said.

"They have survivors' guilt, some of them, saying, 'What should we have done?"' Kraybill said. "It's actually pretty serious in one or two cases."

Gunman Charles C. Roberts IV sent the boys and adults outside Oct. 2 before he tied up the girls and began shooting them inside the heavily barricaded one-room schoolhouse. He shot and killed himself as police closed in.

The Amish were widely praised and admired for their immediate words and gestures of forgiveness, but that has not insulated them from longer-term effects.

Along with the boys' misguided guilt, some have trouble coping with reminders of the shooting, such as helicopters overhead, vehicles that resemble Roberts' pickup and even the presence of strangers, Kraybill said.

The book, "Amish Grace: How Forgiveness Transcended Tragedy," recounts how the Amish immediately assured Roberts' family they held no grudges, comforted his widow at his burial ceremony and set aside some of the donations they received for Roberts' widow and children.

The story of forgiveness inspired people around the world, but the book describes a process that was not as simple as it may have seemed.

"I talked to some people recently: 'Well, we're still working at it.' It's not a done thing," Kraybill said. "(They said) 'We made the commitment, and we expressed the words and did the deeds.' And they would underscore the deeds are more important than the words."

The Amish deeply believe that people must be forgiving toward one another in order for God to forgive them. As a result, soul-searching introspection is not a prerequisite for forgiveness -- not even for a man who shot 10 schoolgirls.

Some of the students and their parents have sought assistance from a counseling center four miles from Nickel Mines, said the center's founder, Jonas Beiler.

"For the Amish people, their ability to forgive keeps them from dragging this into litigation and things of that nature," said Beiler, who was raised Amish. "But that does not mean they don't have to deal with the emotional aftermath or how this upside-down experience has changed their community."

That he was dead and so obviously disturbed simplified matters, said Kraybill's co-author, David L. Weaver-Zercher, a professor of American religious history at Messiah College. But, he cautioned, "Forgiveness is not the end of the story.

"There's other details that continue, and to just wrap it up with that and say (there's) a happy ending to a traumatic thing is too simplistic."

No one at the school could really control what Roberts did, state police Commissioner Jeffrey Miller said. His officers have reassured the children there was nothing they should have done differently.

"We let them know that if they feel that way, they shouldn't," Miller said. "They were just put in an unbelievably horrendous position."

Tragedies such as the Nickel Mines massacre can make survivors feel less powerful and less self-confident, said Marylene Cloitre, professor of child and adolescent psychiatry at New York University's Child Study Center.

"We try to protect our children's sense of their own invulnerability and encourage a belief that people are essentially good," Cloitre said. "These kids at such an early age had a very powerful experience that those things aren't necessarily true."

She said people who are recovering from a traumatic event need to develop a renewed sense of purpose and meaning for their future life.

"In a way, you can say their survivor guilt is the negative consequence of something really wonderful, a sense of community and a sense of responsibility for one another," she said.