TEACHERS spoke out last night after figures revealed a big increase in the number of the region's youngsters arming themselves with knives at school.

Police figures show the number of knives or pointed instruments found in County Durham schools almost doubled between 2003 and last year - there were 34 incidents. This figure looks likely to increase by a third again this year.

The figures were revealed on the day the National Union of Teachers called for action against growing classroom violence at its annual conference in Gateshead.

One teacher described an attack by a 14-year-old girl who tried to kill a member of staff with a kitchen knife.

Yesterday, a teaching union said many more knife and weapon-related incidents go unreported to police because they are dealt with at school.

Sue Percival, national executive member of the National Association of Schoolmasters Union of Women Teachers in Cleveland, said: "Pupils bring in knives, darts and points.

"I would say it happens on average once a week, and I would say a lot more go undiscovered.

"It is very scary if you are a teacher or another pupil at the school."

The comments come after three teenagers at Darlington schools were suspended for carrying knives into school - only hours before an arranged fight had been due to take place between rival gangs.

The two teenagers from Branksome Comprehensive School and a third from Carmel RC Technology College are to be permanently excluded.

In North Yorkshire, there has been a nine-fold increase in children carrying knives and other weapons since 1999.

From 1999 to 2000, there was one incident of a blade or point, and one incident of another weapon in the county's schools.

In the past 11 months, there have been 18 knife or point incidents and nine other weapons.

Cleveland Police were unable to provide figures, but said in the past 11 months there had been five crimes of possession of a knife by a schoolchild and seven crimes of possession of a knife in school.

In 1994, 12-year-old Nikki Conroy was stabbed to death by deranged Stephen Wilkinson in Hall Garth School, in Middlesbrough. Today is the 11th anniversary of her death.

Yesterday, her mother, Diane, said she was shocked by the figures and urged parents to take greater responsibility.

She said: "If we don't talk about it, it is not going to get any better.

"I think we have a collective responsibility - parents, schools, councils and police - but it should start in the home and children should be made aware of the bad things that can happen if they carry knives.

"Nobody should have a knife in school, even if children have to be searched as they go into school."