'We are humbled by this darkness. We feel hopeless, helpless and lost'

The family of the Virginia Tech gunman Cho Seung-Hui spoke for the first time yesterday about the tragedy, saying they felt "hopeless, helpless and lost" and were "heartbroken".

"We never could have envisioned he was capable of so much violence," Cho's sister, Sun-Kyung Cho said on behalf of the family. "We are so deeply sorry for the devastation my brother has caused," she added in a statement released through a lawyer. "No words can express our sadness that 32 innocent people lost their lives this week in such a terrible, senseless tragedy. My brother was quiet and reserved, yet struggled to fit in. He has made the world weep. We are living a nightmare."

The statement goes on to name each of the 32 students and teachers killed by Cho during his shooting rampage on Monday.

"We pray for their families and loved ones who are experiencing so much excruciating grief," it added. "And we pray for those who were injured and for those whose lives are changed forever because of what they witnessed and experienced.

"We are humbled by this darkness. We feel hopeless, helpless and lost. This is someone that I grew up with and loved. Now I feel like I did not know this person."

Cho's family, whose statement amended the gunman's name to Seung-Hui Cho, are under guard at an undisclosed location.

In a television interview, Cho's great aunt in South Korea, Kim Yang-soon, added that he suffered from autism. She said: "[He] did not talk. Normally sons and mothers talk. There was none of that for them. He was very cold. When they went to the United States, they told them it was autism."

Cho's uncle, who wished to be identified only as Kim, said there were no early indications that the South Korean student had serious problems, but said that Cho "didn't talk much when he was young". He added: "He was very quiet, but he did not display any peculiarities to suggest he may have problems. We were concerned about him being too quiet and encouraged him to talk."

As America continued to struggle with the shock of the shootings, and as Virginia held a day of mourning yesterday, former schoolmates and associates of the 23-year-old gunman have told how, as a schoolboy, Cho rarely spoke and was routinely bullied.

When Cho came to the US with his family in the early 1990s, as an eight-year-old, they settled in Centreville, an anonymous commuter town west of Washington DC. His parents worked in a dry cleaners.

Stephanie Roberts, 22, a classmate at Westfield High School in nearby Chantilly, said Cho had been bullied in middle school. "There were just some people who were really mean to him," she said. "They would push him down and laugh at him."

In one of the video messages left by Cho, he said: "Do you know what it feels like to be humiliated and impaled upon the cross? Thanks to you I die like Jesus Christ, to inspire generations of the weak."

Dr Marissa Randozza, a psychologist in Nevada who formerly worked for the US secret service, told The Independent that Cho fitted the pattern of previous school shooters. In 2002 Dr Randozza co-authored a seminal study on school shootings that found that 71 per cent of perpetrators "felt bullied, persecuted or injured by others".

"We found that bullying usually happened closer to the actual shooting [than may have happened in this case]," she said. "In some instances we found that [shooters] were bullied so much it had been a torment, they felt despondent and desperate. It could be this pushed [Cho] into a downward spiral if he experienced bullying before going to Virginia Tech."

The study, carried out in conjunction with the US Department of Education, also found that most shooters had been suicidal before carrying out the attacks.

"We see a fine line between suicide and homicide," added Dr Randozza. "They think things are so bad and they think things will never get better. They look around to see who is responsible for their despair and they think 'I'll take a few with me'."

Indeed, there are even rumours circulating among students that Cho had kept a secret "hit list" of those he wanted to target. "Whether it's a rumour or not, enough people were talking about it so that a lot of people knew that [Cho] had a hit list," Christopher Chomchird, who attended school with Cho, told a chat show.

But other experts say that the bullying that Cho endured for years may not have been the most important issue that drove him to do what he did.

"This is very different from someone who was bullied to the breaking point ­ Cho was clearly psychotic and delusional," said Dr Louis Kraus, chief of child and adolescent psychiatry at Chicago's Rush University Medical Centre.

Dr Kraus said it was more likely that Cho suffered from a biological psychiatric disorder that may have worsened in recent years because of the pressures of university life and being away from his family.

He added: "The type of mental illness that this poor man had was not something that was likely precipitated by teasing or bullying."

In the statement Cho's sister, a Princeton graduate who works for a US State Department office that oversees American aid for Iraq, added: "There is much justified anger and disbelief at what my brother did, and a lot of questions are left unanswered. Our family will continue to co-operate fully and do whatever we can to help authorities understand why these senseless acts happened.

"Our family is so very sorry for my brother's unspeakable actions. It is a terrible tragedy for all of us."

* A gunman shot and killed a hostage, then himself at Nasa's Johnson Space Centre in Houston, Texas, last night. Another hostage is said to have escaped.

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