Gardaí have arrested an armed man in the grounds of a Co Sligo secondary school.
The man, who is reported to be a US citizen, entered Summerhill Boys School in Sligo Town shortly before 2 p.m.
He was dressed in army fatigues and is understood to have been carrying two knives and an imitation firearm.
Two school supervisors tackled the man and tried to escort him off the grounds after he chased pupils in the playground of the school.
But he escaped and ran inside, brandishing what pupils thought was a gun.
Pupil David O'Gorman said: "He came in through the front door. He had the gun down by his side, I was so scared. I just ran up the corridor but luckily enough for me he went up the other corridor."
School Principal Mr Michael Murphy paid tribute to the staff who tackled the armed intruder.
"Because of our fantastic teaching staff and with the assistance of our newly appointed supervisors they quickly brought the situation under control."
It is understood that Mr Murphy had been calling on the Education Department for improved security at the school for the past three years, describing the site as a security risk.
A police spokesman confirmed that a 45-year-old man had been arrested following the incident at the school, which has around 1,000 students.
It is understood that officers recovered a hunting knife with a nine inch blade, two Swiss Army Knives and an imitation firearm.
Gardaí said the man was being detained at Sligo Garda Station and was receiving medical help.