Five people were shot dead and at least 13 injured after a gunman dressed in black opened fire and sprayed bullets around a lecture hall at an Illinois university before killing himself.

The shooter burst from behind a screen during a geology lecture at Northern Illinois University in DeKalb shortly after 3pm and fired on the 160 students using a shotgun and two handguns.

Students frantically scrambled over desks for cover as about 30 rounds were fired across the hall.

University authorities said that the gunman, who has been identified as a student, but not from the university, then turned the gun on himself. Campus police refused to release his name. The incident took place in Cole Hall near the King Commons, a central meeting point on the 25,000student campus.

George Gaynor, a geography student, who was in the class, said that the gunman was “a skinny white guy with a stocking cap on”. He said that it was a chaotic, terrifying scene.

“Some girl got hit in the eye, a guy got hit in the leg,” Mr Gaynor said outside minutes after the shooting occurred. “It was like five minutes before class ended.”

The gunman was said to have been calm as he shot at the students. Some reports claimed that he may have had particular targets. Edward Robinson, another student, said that he seemed to concentrate on one part of the lecture hall. “It was almost like he knew who he wanted to shoot,” Mr Robinson said. “He knew who and where he wanted to be firing at.”

Zach Seward, also a geology student, was near Joe Peterson, a teaching assistant who was injured, when the attack began. “As I was running, I just kept waiting for something to hit me in the back,” he told reporters. “The TA [teaching assistant] looks like half his scalp was gone,” Mr Seward said. “I think I saw him on a stretcher.”

The Kishwaukee Community Hospital received 18 victims — four critical with head wounds — yesterday afternoon. Two were later airlifted to Rockford Memorial Hospital.

The university appeared to have learnt lessons from last year’s Virginia Tech massacre, when Cho Seung Hui went on a rampage killing 32 people before committing suicide — the deadliest school killing in US history.

Within minutes of the first of yesterday’s gunshots, the university had locked down the campus and informed students of the security situation using the intranet and text messages. Police said that they had officers on the scene in less than three minutes.

Mike Digiannantonio was in a campus bus passing Cole Hall around 3.15pm and saw dozens of people racing from the building. “People were saying, ‘Go, go, go, let’s get out of here’.” Linda Stoklasa, 20, said that she also saw students running and screaming, as well as two being treated for wounds outside her dorm. “One kid was bleeding, one girl couldn’t walk.” Fleeing students had told her, “Someone has a gun!”, she said, adding: “I was scared. I was really scared.”

There had been concerns late last year that NIU, about 65 miles west of Chicago, was a possible target for a campus shooting. The university was closed for a day during final exam week in December after police found threats, including racial slurs and references to the shootings at Virginia Tech, scrawled on a bathroom wall. The site was later reopened after an investigation decided that there was no imminent threat.

Yesterday’s shooting is the latest in a string of such incidents to hit American society in the past year. In December Christmas shoppers at a department store in Omaha, Nebraska, fled in terror as a gunman opened fire from a balcony, killing eight people and wounding five before turning the gun on himself. In October six young people were killed by an off-duty sheriff’s deputy at a house party in Crandon, Wisconsin.

Supporters of the American gun lobby have claimed that the Virginia Tech shootings could have been prevented had there been fewer restrictions on firearm ownership.

Newt Gingrich, the Republican former Speaker of the House of Representatives, has claimed that citizens who carry weapons deter would-be shooters. Others have compared the 14,000 people killed by guns in America in 2005 with the total of 50 firearms deaths in England and Wales — which have some of the tightest firearms laws — during that period.

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