British teachers should be wary of following the example of their US counterparts who are transforming classrooms into prison-type structures because of fears of attacks, according to a US security expert.
Delbert Elliott of Colorado University has spent years examining school safety since the Columbine massacre in 1999. He believes that the UK leads the world in its preventative work, praising schools for focusing on community projects instead of metal detectors.
On a recent visit to the UK, he warned that British schools should not believe that CCTV and high-tech security equipment were the best answers. The estimated $10 billion spent on security in the US has effectively been wasted, he said, because shootings still take place.
"Schools have invested heavily but nobody has invested in preventative programmes - people in the US seem to only respond once a tragedy has taken place," said Professor Elliot.
"It's discouraging and frustrating. There are good community programmes but they are not being used widely, and where they are,funding is only in place for a short period of time."
Professor Elliott is a fellow of the American Society of Criminology and director of the Centre for the Study and Prevention of Violence at Colorado University in Boulder, an hour's drive from Columbine.
"The most efficient systems in the US have proved to be those that collect intelligence or hotlines where people can talk anonymously. You also need the police and mental health teams to share information about what's going on in a child's life," he said.
"But most importantly you need a positive school climate where students feel comfortable and people respect them and they feel safe. Metal detectors don't impede attacks if the person is suicidal. In the years since Columbine we've seen schools transformed into jail-like fortresses - this must interfere with the quality of education we can deliver."
Professor Elliott's Blueprints for Violence Prevention programme has helped inspire a preventative scheme being used in Birmingham.
Officials in the city believe that by spending Pounds 41.7 million in areas such as parenting programmes and the appointment of "family nurses", they can save the city at least Pounds 101 million that would have been spent tackling problems caused by violent young people.
Incidents of targeted violence at school are rarely sudden, impulsive acts. Prior to most incidents, other people knew about the attacker's idea or plan, although most attackers did not threaten their targets in advance directly.
There is no accurate or useful "profile" of students who engage in targeted school violence. But most attackers engaged in some behaviour, prior to the incident, that caused concern or indicated a need for help.
Most attackers were known to have difficulty coping with significant losses or personal failures. Many had considered or attempted suicide. Many attackers felt bullied, persecuted or injured by others prior to the attack.
In many cases, other students were involved in some capacity.
From the findings of the Safe School Initiative conducted by the US Secret Service and US Department of Education.