ROCKVILLE, Md. (DC News Now) — Three students from College Gardens Elementary School were hospitalized after ingesting what police believe were methamphetamines.

Rockville City police and Montgomery County police responded to the school in the 1700 block of Yale Place on Monday.

School officials tell DC News Now it happened at the playground at the school.

Investigators said the students found a container of blue items they believed to be candy. Three 7-year-old students ingested the substance briefly before spitting it out.

The students began to feel dizzy, at which point they alerted the school nurse, who called EMS.

“I got an email from the school that they found three children had reactions to candy,” said Samantha Debourgh, a parent with a child at College Gardens Elementary.

The substance was not recovered. Detectives weren’t able to determine exactly what the students consumed. Based on the toxicology of the victims, investigators believe the substance may have been methamphetamine.

“I am relieved that the students will ultimately be fine, but in many ways, what happened today is frightening,” said Chief Marcus Jones. “I hope that it serves as a powerful motivator for parents to keep having the difficult conversations with their children about the dangers of taking or eating unknown substances.”

Debourgh said she was astonished to hear the drugs could be methamphetamine-related drugs.

School officials reminded parents to tell their children only to eat food brought from their own homes. 

“This is something I always have to keep reminding her of also. Cause kids tend to share,” said Debourgh. “I’m just grateful it wasn’t her. I’m sorry for the others who got impacted by that,” she added.

All three students were discharged from the hospital and returned home to their parents.