In the quiet Houston suburb of Galena Park, Texas, uniformed police with two-way radios meet arriving youngsters every day when they report for school. All doors to the school building are locked from the inside, students are required to carry identification cards and boys are banned from wearing facial hair so that outsiders can be more easily identified.

Such security measures are a fact of life for millions of American schoolchildren, and no longer only in the inner cities.

“Our society has reached the point where school systems have had to get into the police business,” said Brian Clemens, Galena Park’s school security director.

More than 50 killings and suicides occurred last year at or near US schools, according to the US Centers for Disease Control and Prevention, which keep track of death statistics. They were among a total of three million reported crimes in and around American schools, ranging from assault to weapons offences.

Educators have responded by installing metal detectors, surveillance cameras, motion sensors to detect intruders, security bars on the windows to prevent break-ins, using bar-coded identification cards, uniformed police, drug-sniffing dogs, and carrying out random searches.

Eighty-two per cent of 729 districts surveyed by the National School Boards Association said violence in schools has increased in each of the past five years. Fifteen per cent said they use metal detectors to screen for weapons. The association said that “an epidemic of violence” had besieged American schools.

“There was a time you never heard of such a thing as school security. It did not exist,” said an Association spokesman. “Now violence is potentially a problem everywhere.”

Take Welch, West Virginia, for instance. A small town of 4,000 people in the Appalachian Mountains, the community has two uniformed security guards posted in its high school, which is equipped with metal detectors and 30 surveillance cameras. Identification cards are required to enter the building. The measures were added after a 17-year-old student pulled out a .25-calibre handgun and wounded a classmate.

This level of security has critics among civil libertarians, who say it turns schools into prisons.

In August, a court upheld the right of the school district in Miami to conduct random searches using hand-held metal detectors. A federal appeals court judge ruled that such measures had become “commonplace to everyday living”.

But critics won a victory last month when a New York court ruled that a 15-year-old boy caught with a loaded pistol in school should not have been suspended, since he was searched illegally by a security guard without probable cause or due process.

Last year, in the New York City schools alone, there were 1,977 incidents of assault and 6,920 weapons seized, including 129 handguns. One school, Thomas Jefferson High School in Brooklyn, has had to stagger the starting times for its 1,500 students so they can all file through the X-ray machines, installed after three students were killed and a teacher injured in two separate shootings in 1992.

A survey last year in New York State found that nearly a quarter of the students there felt unsafe in school, 18 per cent had been assaulted on school grounds, 52 per cent said they had observed other students carrying guns or other dangerous weapons and 37 per cent said they were aware of cases in which students had dropped out because of fear of violence.