Warning signs about Seung Hui Cho came early in his life.

Cho was unusually quiet as a child, relatives said. He did not respond to greetings. He did not want to be hugged. But when Cho fought with his older sister, he would punch her with shocking violence.

Kim Yang Soon, a great-aunt in Korea, said Cho's mother told her the boy had autism. After the family immigrated to the United States in 1992, when Cho was 8, Kim would call his mother and ask how the boy was doing. "She only talked about her daughter," Kim said. "We knew something was wrong."

Because Cho did well in school, his mother did not seem very determined to get treatment for him, Kim added.

It is unknown what, if any, help the parents sought for their son before he attended Virginia Tech, where this week Cho killed 32 schoolmates and teachers. The Chos left their home in western Fairfax County the day of the shootings and are staying at an undisclosed location. Only a few friends are in contact with the family, and most have declined to talk, upon the Chos' request.

The Chos spoke for the first time yesterday, releasing a statement to the Associated Press through an attorney, saying they feel "hopeless, helpless and lost" and "are so deeply sorry for the devastation" caused by the gunman.

"We are humbled by this darkness," wrote Cho's sister, Sun Kyung Cho, 25. "This is someone that I grew up with and loved. Now I feel like I didn't know this person. . . . My brother was quiet and reserved, yet struggled to fit in. We never could have envisioned that he was capable of so much violence."

Before Monday, when Cho went on his shooting rampage, the family's story was not so different from that of other Korean immigrants.

Seung Tae Cho and his wife, Hyang In, told friends they came to America for the sake of their children's education. They settled in a townhouse in Centreville near good public schools. The father worked long hours pressing pants at a dry cleaner in Manassas. The mother occasionally went to church.

And when their firstborn, Sun Kyung, got into Princeton in 1999, it seemed as if all their sacrifices had paid off. The parents, once adrift in poverty in South Korea, now had an anchor for the good life in America through their Ivy League daughter.

Beyond these broad brush strokes of Cho's life in Fairfax, only bits and pieces have emerged from relatives. The local ethnic organizations that typically gather Korean immigrants -- churches, social clubs and civic associations -- say the Chos were largely unknown and disconnected in the Washington area, which is unusual for the tight-knit community.

"They're like ghosts," said Ron Kim of the Korean-American Dry Cleaners Association of Greater Washington. "It is really strange for a family not to be known."