'Sad' era of classroom panic alarms.
Panic buttons could soon be a common feature in classrooms in Wales, teachers' leaders warn.
Threats to the safety of children, as well as school staff, are now on the increase, teaching unions will announce today.
It is such a 'sad state of affairs' that one school has now been given a panic button by police after warnings that a pupil was in danger of being 'snatched' from school.
Rhys Williams, spokesman for NUT Cymru, said that in 'extreme circumstances we can see there is a justification for panic buttons'.
'There have been cases, particularly in schools where there are severe discipline problems, where we have called for panic buttons so that help can be obtained by teachers,' he added.
'Sadly there will be cases where teachers have been assaulted or they feel under threat so we support anything that increases the safety in schools.'
One school in Rhondda Cynon Taf has had to install a safety device to protect a child after a parent threatened to 'snatch' them. An 'AlertBox' has been installed in the child's classroom, which is radio-linked to another in the secretary's office.
Should the teacher become at all concerned, she can press a button on the box - which is the size of a paperback book - which immediately sends a 'help' message to the secretary.
In the past decade security has been increased after several schools around the country were entered by violent intruders.
But teachers' leaders say it is not uncommon for the threat to come directly from parents. And as parents' relationships break down, teachers are finding they get caught in the crossfire and will be put in the uncomfortable position of mediator.
'There have been cases where the school will look after a child until the mother comes and takes the child from the care of the teacher,' said Mr Williams.
'Schools are an oasis of calm in a turbulent society, but it can be hard work hanging on to that.'
Geraint Davies, secretary of NASUWT Cymru, said it was a 'sad day' when teachers and pupils had to be protected in this way from possible intruders.
'Although this is the first in Wales. It might not be long until we see widespread use of these panic buttons.'
The panic button in the school in Wales was supplied by the local Community Safety Partnership, after a parent threatened to snatch their child on their release from prison, and will be used as part of its armoury against anti-social and criminal behaviour.
As one of the first local authorities to trial the AlertBoxes, RCT has also placed two devices in a magistrate's court to protect vulnerable witnesses.
A surgery in Cynon Valley is also using the device because staff regularly deal with volatile patients with drug and alcohol problems.
Elderly women running a community centre in the authority can also use it to summon help should they feel threatened at night.