A Co Donegal school principal yesterday described as "sinister and specific" a bomb warning recorded on his school's telephone answering system.
Paul Fiorentini was speaking after Carndonagh Community School in Inishowen was evacuated and closed for the second day in a row as a result of bomb warnings.
Over 1,000 pupils and members of staff were sent home yesterday and on Wednesday following the warnings. The nearby national school was also evacuated and its 150 pupils and teachers sent home.
Gardaí accompanied by members of the community school's staff searched the building following the latest warning, but nothing was found.
Mr Fiorentini described both incidents as "acts of terrorism" which, he said, were aimed at "sabotaging the life of the school". The principal said he was shocked when he played the message on the answering system for the second successive day.
"This is a very stressful time for the students, for their parents and for my staff. We do not see it as a joke, the students do not see it as a joke and their parents do not see it as a joke. It is an act of terrorism, it is sinister and the person behind this knows the outcome of their actions.
"The gardaí are carrying out their inquiries, and we hope and pray that whoever is responsible will be found. The scenes at the school caused by these phone messages have been dreadful to witness. The threat is very direct."
Mr Fiorentini added: "It has been a very distressing two days for everyone involved.
"Yesterday was one of the highlights of the year when pupils got their Junior Cert results - then it all had to be abandoned."