Intruder sparks Hampshire Wyvern College lockdown
Pupils were placed in lockdown when an unarmed intruder entered a school's grounds.
The man, who did not make any threats, was seen at Wyvern College in Fair Oak, Hampshire, at about 09:15 BST, the school said.
Head teacher Ben Rule said staff supervised the intruder, who was not known to anyone at the school.
Hampshire police said officers later located an 18-year-old man who had left the grounds.
A force spokeswoman said inquiries were continuing.
Mr Rule said the intruder was on the secondary school's field and was kept away from buildings by five members of staff.
The school's medical staff also helped the man, who twice collapsed to the ground, before he was treated by an ambulance crew.
Students were kept in their first lesson until the matter was dealt with before they were allowed to carry on their day, Mr Rule said.
In a letter to parents, he said: "There is already a lot of misinformation on social media about this incident [but] I can report that this intruder carried no weapon and was under close supervision from when he came on site."
The school was working with Hampshire County Council to improve security at the site, he added.
Wyvern College has more than 1,300 pupils aged 11-16.