The principal of Riverhead High School is warning parents that a "potentially harmful, ingestible substance may be circulating through the school community and accessible to students."

In a letter to parents obtained by News 12, Principal Sean O’Hara says there is limited information on the actual substance and how students are getting their hands on it.

O'Hara released a statement, saying in part: "As a district, we are taking proactive steps to mitigate this matter internally, including partnering with law enforcement to further investigate the matter."

According to Riverhead Police Chief David Hegermiller, on Feb. 4 and 10, two students passed out in school. Narcan, a medication that reverses opioid overdoses, was used in both incidents.

"I heard something about fentanyl being used, and it's just scary to think about that this is happening," says senior Hunter Hughes.

Parents are concerned that vaping has been an issue at the school.

"We have to be more conscious that drugs are all over the place now," says Riverhead mother Dilsia Gonzalez.

James Alfano, with the Riverhead Volunteer Ambulance Corporation, says the student who was unconscious on Feb. 10 was in the hallway and denied vaping. The other student was in a classroom and admitted to vaping.

Both teens regained consciousness at the school and were transported to the Peconic Bay Medical Center.

Dr. Jeffrey Reynolds, with Family and Children's Association, is an expert at treating drug addiction,. He says he would guess that the opioid being used is fentanyl.

Reynolds says the pandemic is pushing more young people to use drugs and is taking away potentially lifesaving educational programs.

"The prevention programs that used to happen in auditoriums and the parents' nights that used to happen are no longer happening in a COVID environment," Reynolds says. "So that means kids are left anxious, depressed and without the requisite education as are their parents."

An ambulance was also at the school Monday. News 12 is told it was for a student who ate a chocolate edible.

Narcan was not needed in the case.

Parents are being encouraged by the school to speak with their children about being aware of their surroundings and the consequences of their actions.

"Parents need to talk to their kids all the time, regardless of if there's a new substance or not," says Cathleen Sellers.

The district says it is partnering with law enforcement to mitigate the matter and to develop a quick resolution. Students are being advised not to take any unknown items from others and to report suspicious behaviors immediately.

The principal wrote a letter to parents Monday, saying "We will be hosting a virtual assembly for students about the dangers of alcohol and drug usage, and we will be offering training opportunities for our administrators and any interested staff members."

Reynolds says the assembly will need to include lessons about how to administer Narcan.

"It's akin to teaching your staff and students CPR so they can save somebody else's life," Reynolds says.

The dates for the virtual assemblies have not been announced.