The country's biggest teaching union has backed the findings of a survey which found that attacks on staff by parents is on the rise in the region.

The National Union of Teachers said it was "worried and alarmed" by an increasing number of assaults on teachers.

An on-line survey by education website found that almost one in ten of respondents in the North-East had been physically attacked by angry parents.

About a third said they had been verbally abused in confrontations at school. Elaine Kay, principal officer for the NUT in the North-East region, said: "We are aware of teachers finding themselves in situations where they are subject to abuse.

"A larger number of teachers are subject to verbal abuse, but we have of course members who have been the victim of physical attack."

Teachers say that often violent and abusive parents seeking to engage in confrontations are under the influence of alcohol or drugs.

They may have been angered by a child's disciplining at school or simply their failure to make the grade academically.

The survey also found more than half of the teachers questioned would not make a complaint if they had been abused.

Hurworth School is one of the top performing schools in the country and lies in an affluent area of Darlington.

Its academic success is measured in the fact that it came tenth in a Department for Education and Skills league table published this week for the most improved schools in the country.

Despite such success headteacher, Eamonn Farrar, who joined the school six years ago, will still admit to a problem with abusive parents which he has faced directly himself.

He said: "It is a small one for us, but definitely an issue that needs to be drawn to people's attention.

"I have been threatened myself by people threatening to kick my teeth in. "Once I had a guy go nose to nose with me in the main foyer here in front of my pupils and I fully expected him to attack me at any moment."

Mr Farrar adds he has suffered a torrent of abuse from a parent whose pupil he excluded.

He believes the issue is indicative of a wider problem in society. "There is a growing culture developing where people feel that it is all right to vent your anger on public servants and we've seen it with doctors and hospital staff.

"Here though we have good discipline and high expectations and it is time that people actually said we will not put up with this sort of thing."