Dazed and stricken, the Virginia Tech community struggled Tuesday to come to grips with the murders of 32 friends and colleagues, as details emerged about the loner who unleashed terror on the bucolic campus.

Students fought back tears, walked quietly around the sprawling campus and greeted one another with hugs. Their classes canceled for the week, many packed their things to head for the security of home.

Emotions were raw among the 10,000 who gathered in the basketball arena for a nationally televised midday memorial service. An overflow crowd packed the football stadium.

“Today, the world shares our sorrow,” said Zenobia Hikes, the vice president of student affairs.

Outside, faculty members described the gunman – whom authorities identified as 23-year-old senior Cho Seung-Hui – as troubled, and students said they barely knew him.

Inside the service, President Bush symbolized the nation’s anguish.

“It’s impossible to make sense of such violence and suffering,” Bush said in nine-minute remarks. “Those whose lives were taken did nothing to deserve their fate. They were simply in the wrong place at the wrong time. Now they’re gone, and they leave behind grieving families and grieving classmates and a grieving nation.”

‘He was a loner’

A chilling picture emerged Tuesday of Cho, a senior majoring in English, a day after the bloodbath that left 33 people dead, including Cho, who killed himself as police closed in.

News reports said that he may have been taking medication for depression and that he was becoming increasingly violent and erratic.

Despite the many warning signs that came to light in the bloody aftermath, police and university officials offered no clues as to exactly what set Cho off on the deadliest shooting rampage in modern U.S. history.

“He was a loner, and we’re having difficulty finding information about him,” school spokesman Larry Hincker said.

A student who attended Virginia Tech last fall provided obscenity- and violence-laced screenplays that he said Cho wrote as part of a playwriting class they both took. One was about a fight between a stepson and his stepfather, and involved throwing of hammers and attacks with a chainsaw. Another was about students fantasizing about stalking and killing a teacher who sexually molested them.

“When we read Cho’s plays, it was like something out of a nightmare. The plays had really twisted, macabre violence that used weapons I wouldn’t have even thought of,” former classmate Ian MacFarlane, now an AOL employee, wrote in a blog posted on an AOL Web site. He said he and other students “were talking to each other with serious worry about whether he could be a school shooter.”

“We always joked we were just waiting for him to do something, waiting to hear about something he did,” said another classmate, Stephanie Derry. “But when I got the call it was Cho who had done this, I started crying, bawling.”

Referred for counseling

Professor Carolyn Rude, chairwoman of the university’s English department, said Cho’s writing was so disturbing that he had been referred to the university’s counseling service.

“Sometimes, in creative writing, people reveal things and you never know if it’s creative or if they’re describing things, if they’re imagining things or just how real it might be,” Rude said. “But we’re all alert to not ignore things like this.”

She said she did not know when he was referred for counseling, or what the outcome was. Rude refused to release any of his writings or his grades, citing privacy laws. The counseling service refused to comment.

Cho – who arrived in the United States as boy from South Korea in 1992 and was raised in suburban Washington, D.C., where his parents worked at a dry cleaners – left a note that was found after the bloodbath.

President Bush, right, signs a memorial for Virginia Tech shooting victims. With him Tuesday, from left, are first lady Laura Bush, Anne Holton, wife of Virginia Gov. Timothy Kaine, and Kaine.

A law enforcement official who read Cho’s note described it Tuesday as a typed, eight-page rant against rich kids and religion. The official spoke on condition of anonymity because he was not authorized to speak to the media.

“You caused me to do this,” the official quoted the note as saying.

Cho indicated in his letter that the end was near and that there was a deed to be done, the official said. He also expressed disappointment in his own religion, and made several references to Christianity, the official said.

The official said the letter was either found in Cho’s dorm room or in his backpack. The backpack was found in the hallway of the classroom building where the shootings happened, and contained several rounds of ammunition, the official said.

Col. Steve Flaherty, superintendent of the Virginia State Police, said authorities were going through a considerable number of writings.

Recent bomb threats

Monday’s rampage consisted of two attacks, more than two hours apart – first at a dormitory, where two people were killed, then inside a classroom building, where 31 people, including Cho, died. Two handguns – a 9 mm and a .22-caliber – were found in the classroom building.

The Washington Post quoted law enforcement sources as saying Cho died with the words “Ismail Ax” in red ink on one of his arms, but they were not sure what that meant.

According to court papers, police found a “bomb threat” note – directed at engineering school buildings – near the victims in the classroom building. In the past three weeks, Virginia Tech was hit with two other bomb threats. Investigators have not connected those earlier threats to Cho.

Cho graduated from Westfield High School in Chantilly, Va., in 2003. His family lived in an off-white, two-story townhouse in Centreville, Va.

“He was very quiet, always by himself,” neighbor Abdul Shash said. Shash said Cho spent a lot of his free time playing basketball and would not respond if someone greeted him.

Classmates painted a similar picture. Some said that on the first day of a British literature class last year, the 30 or so students went around and introduced themselves. When it was Cho’s turn, he didn’t speak.

On the sign-in sheet where everyone else had written their names, Cho had written a question mark. “Is your name, ‘Question mark?”‘ classmate Julie Poole recalled the professor asking. The young man offered little response.

Cho spent much of that class sitting in the back of the room, wearing a hat and seldom participating. In a small department, Cho distinguished himself for being anonymous. “He didn’t reach out to anyone. He never talked,” Poole said.

“We just really knew him as the question mark kid,” Poole said.

Legal gun purchases

State police said Cho had legally purchased the two handguns found with his body, a Walther P22 and Glock 9 mm. One of the weapons was used in both the initial shooting of two people at a dorm and the murders of 30 others in a classroom building.

Affidavits for search warrants filed with Montgomery County Circuit Court said police thought that Cho also had written a bomb threat against Virginia Tech’s engineering school classes, which they found at the scene of the shootings. The school had been troubled in recent weeks by bomb threats, but police didn’t say whether they thought Cho was behind them.

Stories of heroism

Stories of heroism and ingenuity emerged Tuesday.

Liviu Librescu, an Israeli engineering and math lecturer, was killed after he was said to have protected his students’ lives by blocking the doorway of his classroom from the gunman. And one student, an Eagle Scout, probably saved his own life by using an electrical cord as a tourniquet around his bleeding thigh, a doctor reported.

On Tuesday night as darkness fell, thousands of Virginia Tech students, faculty and area residents poured into the center of campus to grieve together. They held thousands of candles aloft as speakers urged them to find solace in one another.

Most of the vigil was devoted to silence and quiet reflection. As the silence spread across the grassy bowl of the drill field, a pair of trumpets began to play taps. A few in the crowd began to sing Amazing Grace.

“We will move on from this. But it will take the strength of each other to do that,” said Zenobia Hikes, vice president for student affairs. “We want the world to know we are Virginia Tech, we will recover, we will survive with your prayers.”