Lauralton Hall in Milford dismissed early on Tuesday afternoon after pepper spray was discharged in the building, which sent some students to the hospital.
The incident was reported at Lauralton Hall, which is an all girls Catholic school, around 10:15 a.m. Authorities said at that time, between 30 to 40 students were changing classes and were in the main area of Lauralton Hall.
Authorities said the pepper spray, which is a fine mist, propelled through the air and some students reported injuries. However, no staff or teachers were injured. A classmate was reportedly showing her pepper spray to friends.
"To my understanding this happened in between class changes and there were a lot of people congregating in that area at that particular time who happened to walk through the cloud of irritant that was discharged," said Milford Batallion Chief Anthony Fabrizi.
"She was going to spray it on the floor just to see what it was like and three people were like 'don't do that' and she was like 'I'm just going to do it anyway,' so she sprayed it on the floor and it had a reaction and everyone in the Mercy Hall building got affected," said student Marianna Bischoff.
Authorities said no one was sprayed in the face.
Six students were taken to Milford Hospital where officials said they will be evaluated, briefly treated and discharged.
Officials at Bridgeport Hospital said they have not received any patients from Lauralton Hall, but they were on standby.
The pepper spray incident remains under investigation. The school's ventilation system was checked out and is clear.
Classes will be back in session on Wednesday as normal.
Some of the girls who take the train to school said they do carry pepper spray for safety, but it is not clear if the school has any policy about whether it is allowed inside the school or not.
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