Police and ambulances were called to the Outwood Academy Ripon as students started collapsing shortly after 11a.m., according to the U.K. publication The Independent.
The school confirmed that four children collapsed during an Armistice Day service and at least 40 were treated on site, according to BBC News.
“At this time, the safety of all the students and staff at the school is paramount and officers are working with the fire and ambulance services to establish what has caused the students to collapse,” a spokesperson for North Yorkshire Police stated.
Police reportedly stated that they were aware of at least two pupils who attended hospital or local medical facilities independently. Crews from Ripon and Boroughbridge along with hazardous materials specialists and detection teams were sent, according to the North Yorkshire Fire and Rescue Service.
“When the first boy was sick, we thought it was one off but then there was a big slap on the floor and someone had fainted,” stated one student.
“After that it was a bit of a domino effect, another three or four collapsed and then people started leaving the hall to get fresh air. One of the boys who fell was a bit concussed and had a big lump on his head. After that they ushered us out quickly and a couple of girls had panic attacks."
Classes were reportedly resumed in the afternoon, but more students complained of feeling sick and suffering from headaches throughout the day.
No chemicals or gases had been detected in the recent scare, according to reports. A fire officer told BBC News that they believed the hall “was a hot room and some children had become overwhelmed.”
“We are of the view the children just fainted and there was a ripple effect throughout the school,” explained fire station manager Dave Winspear.