Today's lesson: how to survive school shooting

At least 500 colleges are showing a survival video created in the wake of the Virginia Tech and Northern Illinois shootings that killed dozens of students and teachers.

The 20-minute video, entitled Shots Fired On Campus, begins with a macabre reconstruction of a suicidal teenager opening fire in a classroom.

It comes amid rising concern about school shootings across America.

Last year on 16 April Seung-Hui Cho launched the deadliest attack when he killed 32 and wounded many others before committing suicide on the campus of Virginia Polytechnic Institute.

Then on 14 February at Northern Illinois University, Steven Kazmierczak killed six - including himself - and wounded 18.

The video's maker, Randy Spivey - a former hostage negotiator who now runs a private security firm - denied he was profiteering from paranoia and said he wanted students to learn to "get out, hide out or take out" (make use of superior numbers to disable the attacker).

Mr Spivey said: "If you look at Virginia Tech, most of the shootings took place in a second-floor classroom with windows.

"The shooter came in, shot a couple of people, and then left. He came back later and killed more of them.

"If they had been thinking about their options properly, they might very well have decided to climb out of the window.

"The difference between trained and untrained people in a crisis situation is that untrained ones will panic.

"But if they were acting logically they might realise that if you have one gunman in a room full of 200 people, the odds are very much in the favour of the 200 people."

Tim Walters, chief of police at Eastern Washington University, said the video was like a "fire drill".

He said: "Fires are rare but we still do fire drills all the time.

"Why shouldn't we train our kids what to do to survive an active shooting situation?"