Police in Ontario say that two elementary students were sent to hospital after a child took his or her parent’s cannabis cookies to school.

Durham Regional Police Service says that the incident happened on Wednesday at Hillsdale Public School in Oshawa, Ont.

“One of the students snuck several cookies into school and had ingested them with a friend,” police said in a news release. “Both senior students … became ill and were transported to a local hospital where they remained overnight for observation,” the release goes on.

Police say a parent with a medical cannabis license had made the cookies and they were taken without consent.

The Children’s Aid Society is expected to conduct a review, according to police.

“Officers have also taken the time to educate students, parents, caregivers and teachers about the dangers and risks of consuming psychoactive chemicals at such an early age,” the release states.

Durham District School Board also confirmed the incident in a news release.

“The student who brought the cookies and a friend exhibited signs of consumption and impairment, and were taken to hospital where they were monitored for elevated heart rates,” the school board said.

“Recent legislation has not had a significant impact on how schools are dealing with incidents involving cannabis,” the school board added.

Health Canada reports that short-term health effects of cannabis use may include psychotic episodes, low blood pressure, anxiety, confusion and sleepiness. Long-term cannabis consumption can lead to addiction, memory problems, concentration problems, lowered IQ, difficulty thinking and making decisions, and respiratory problems, they say.

Youth are particularly vulnerable to developing mental illnesses and brain effects from cannabis because the brain is not fully developed until around age 25, according to Health Canada.