A Briton who taught the Virginia Tech gunman said yesterday that she had repeatedly warned university authorities that he was deeply disturbed, but that her pleas for help were ignored.

Lucinda Roy, head of the English department at Virginia Tech until last year, spoke to The Times as police admitted that Cho Seung Hui was interviewed twice for stalking two female students and was committed to a mental health facility briefly in December 2005.

Police were studying the list of victims last night for a possible connection to Cho after it emerged that he and two of the dead had attended the same school, Westfield High in Virginia. One victim, Reema Samaha, a ballet dancer, grew up in Centreville, Virginia, two minutes from Cho’s home.

Wendell Flinchum, the police chief of the university, said that the first stalking complaint came on November 12, 2005, after Cho sent “annoying” messages to a student. Another student complained the next month.

After speaking to Cho “at length”, he became concerned that the student might be suicidal. A temporary detention order was taken out when the South Korean agreed to counselling. He was taken to a mental health facility but released soon afterwards.

Professor Roy said that she and her students became so concerned about Cho’s violent writings and menacing behaviour that she took him out of her class and gave him one-on-one tuition in English.

She and another teacher expressed so many concerns about Cho that in 2005 the university offered them protection, but they turned it down.

Professor Roy, from Battersea, South London, said that Cho was the most disturbed student she had encountered in her 22 years at Virginia Tech. She had pleaded repeatedly with the university to give him counselling. But because he had not threatened anybody directly, the authorities were powerless to help.

She said that Cho would arrive in class wearing dark glasses, a maroon Virginia Tech hood pulled down over his head. He never volunteered a word, always looked down and used his mobile phone to take “inappropriate” photographs of the female students from under the desks. He refused to respond to his real name and wanted to be known as “Question Mark”.

“For the most part he wouldn’t speak to people, so if you asked him something he would sometimes take as long as 20 seconds to answer, and then only in a whisper,” Professor Roy said. Cho’s writings were full of anger.

She said that she went to university police and counsellors repeatedly and sent Cho’s writings, poetry and plays — full of violence and twisted sexuality — to the police “to alert them and share my worries with them”.

Professor Roy said: “They would say there’s no explicit threat here, so nothing was done. They couldn’t compel him to attend counselling.”

She added: “I was concerned that he was suicidal, that he was depressed. There was a negativity. It was like talking to a hole. There was such an absence when he entered a room. Everything just emptied out and it turned very dark.” Her students were so uncomfortable that in October 2005 she took Cho out of class and gave him three lessons alone.

Only once did Cho open up, giving a glimpse of the turmoil behind the blank look. “At one point he did admit to me that he was lonely and that he didn’t have any friends,” Professor Roy said. “He also said, ‘I’m really shy and it’s just very hard for me to talk.’ I told him I understood and that being acutely shy was torture.”

Professor Roy said that she would be haunted for the rest of her life about whether she could have done more to stop the massacre. “I think we did the best we could. But having failed to protect the students, there is a great wound.”

Nikki Giovanni, a poet who taught Cho creative writing, said that she threatened to resign unless he was removed from her class. He took inappropriate pictures of female students and talked repeatedly about death. One day only seven of her seventy students turned up. She was told that it was because they were afraid of Cho. “I wanted him out of my classroom,” Ms Giovanni said.

She said that his poetry was “intimidating” and “there was something mean about this boy. I’ve taught troubled youngsters. He was mean”.

She contacted Professor Roy and Cho was removed from the class. Ms Giovanni said that she never felt that Cho was a physical threat, but added: “I knew when it happened that that’s probably who it was.”

Asked about Cho’s troubling plays and poems, Mr Flinchum said that no official report had been filed. “These assignments were for a creative-writing course and the students were encouraged to be imaginative and artistic,” he said. “The writings did not express any threatening intentions or allude to criminal activity. No criminal violation had taken place.”

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