Tuesday, May 4, 1999 Published at 11:44 GMT 12:44 UK
Threats disrupting US classes
Security checks at a school in New York State
There has been constant disruption to schools across the United States as a result of 'copycat' threats following the shootings at Columbine High School in Denver.
Officials say that the climate following the murders is such that they feel they have to take seriously what might otherwise have been dismissed as nuisance calls or letters.
"Some schools have been more sensitive about it, but when it comes to security measures there's no such thing as overreacting," said Jesus Villahermosa, a deputy sheriff in Pierce County, Washington, who advises schools on security issues.
He said at least 14 people around the state were arrested last week for bomb threats to schools.
The President of the Washington Teachers Union, Barbara Bullock, said teachers were having difficulty keeping lessons on track because most of the older students did not return to a school if it had been cleared because of a threat.
"It's really interrupting instructional time," she said. "But God forbid the day you decide to ignore it."
In Charlotte, North Carolina, classes and SAT college entrance exams due to take place at four schools on Friday had to be cancelled. Police spent the weekend checking school campuses to make sure they were safe.
Officials hope that eventually peer pressure will stop the pranksters, as pupils get fed up with having their lessons, tests and out-of-school activities postponed or dropped.
Mr Villahermosa said a student who had pulled the fire alarm at his school about a dozen times in the past two weeks had been caught because some of his fellow pupils turned him in.
"They just got so tired of it," he said.