CHICAGO (CBS) — At least 14 elementary school students were taken to the hospital after pepper spray was discharged in their Gresham school Wednesday morning, authorities say.

Chicago police say officers responded to Gresham Elementary in the 8500 block of South Green Street around 11:30 a.m. for reports of pepper spray being sprayed. Police say the students were taken to St. Bernard, Advocate Trinity and Little Company of Mary hospitals for eye irritation and shortness of breath.

Chicago Public Schools said in a statement:

“The safety of our students is the district’s top priority and school staff alerted emergency responders immediately after an aerosol irritant was released inside one classroom. Several students were transported to the hospital out of an abundance of caution and the school has notified the parents of affected students. The individual responsible has been identified and the situation will be handled in accordance with CPS policy. The district is dedicated to creating safe school environments and we are working with the school to implement additional safety measures.”

Four similar incidents have been reported at Morgan Park High School in the past week.

On Wednesday, a level one hazmat was called at the high school after a substance was sprayed or released into the air, according to a Chicago Fire Department spokesperson.

Two students were taken to the hospital Tuesday afternoon, after someone sprayed an unknown substance at the school.

Last week, police and fire crews were called to the high school two days in a row — on Thursday and Friday — after students were sprayed with an aerosol irritant, possibly pepper spray or mace.