TURNER, ORE. -- More than 42 years after a Japanese balloon bomb killed five children and a pregnant woman on a church picnic in southern Oregon, seven of the Japanese women who made the balloon have sent letters of condolence to families of the victims.

The letters, brought to the United States from Japan by a university professor who spent the war in an internment camp in California, were accompanied by 1,000 folded paper cranes, a Japanese symbol of peace and healing.

For Nyle Gifford, whose 13-year-old son, Jay, died in the 1945 explosion, the letters were a surprise.

"I never felt angry," said Gifford, 85. "We were Christians, and we were forgiving."

For University of Michigan sociologist Yuzuru Takeshita, now 61, they were a way to help heal the wounds of World War II.

On May 5, 1945, the Rev. Archie Mitchell, his wife and five children from a church Sunday school were picnicking on the slopes of Gearhart Mountain near Bly when they found a shiny object: a bomb attached to a hydrogen balloon made of rice paper.

As they gathered around, it exploded, killing the children, ages 11 to 14, and the pastor's 26-year-old pregnant wife.

They were the only people to die in a World War II attack on the continental United States.

Takeshita, then in a northern California camp for Japanese Americans, heard that the Japanese had sent balloon bombs across the Pacific.

"We had nothing much to do, so we spent all day looking for them. Some people say they saw them, but I never did," he said.

His search for survivors of the victims of the Oregon bombing and for those who made the balloons began four years ago when he was on a research trip to Southeast Asia.

A friend's wife told him that as a schoolgirl she helped make the balloons, adding that she had heard that one of them fell in the United States and was on display at the Smithsonian Institution.

On a trip to Washington, Takeshita found a picture of the balloon bombs and took a photograph of it. He attached a list of names of the Bly victims and sent it to Japan, where he asked friends to pray for the victims.

Last year, Takeshita returned to Japan, and saw on television an old woman who said she had been a schoolteacher during the war and her students had made balloons. He later saw the woman, and sent her the list of victims and the request for prayers.

Last August, she wrote to tell him she and some of her former coworkers had got together to start folding 1,000 paper cranes.

In September, Takeshita carried the cranes and letters of condolence from the women to some of the relatives of the victims, who were gathered at a memorial to the victims in Bly.

"These one thousand cranes were folded one by one by some of us who made the balloon bombs, seeking forgiveness and with prayer for peace and a vow that the error of the past shall never again be repeated," said one letter.

According to the letters, the women had been taken from high school classrooms and sent to a war plant to build the balloons "without understanding much beyond the knowledge that America was our adversary in war."

The realization that a woman and five children had died "truly sent a chill down my spine," wrote Tetsuko Tanaka.

Katsuko Maeda, 16 at the time, wrote that her involvement in making the balloon bombs as "part of the all-out war effort."

For those who died on the mountain, "I pray for them from the hills of far-away Japan, with a fervent wish for peace around the world."