Police are investigating after a five-year-old boy in Ohio was exposed to methamphetamine Sunday night, and the boy’s parents say the Halloween candy may be to blame.

The boy was hospitalized Sunday evening and treated for consuming the illegal drug shortly after he went trick-or-treating in his neighborhood, WCMH reported.

“(We) found out the child had tested positive for methamphetamine in his system,” Galion Police Chief Brian Saterfield said.

Authorities are trying to determine whether the child ingested candy laced with meth, but the boy’s parents told the police he had been playing with plastic vampire teeth stashed in his trick-or-treat haul. Moments later, the child began having a seizure.

Doctors at the hospital discovered the child had traces of meth in his urine and kept him hospitalized for seven hours.

The child’s candy had been sent to a crime lab for testing after the incident, police said.

Police departments around the country are urging parents to check their child’s trick-or-treat bags for suspicious looking candies to prevent instances of drug poisoning.

“(We are) asking people to double-check their children’s candy supply that they receive while trick-or-treating, and if there is anything suspicious, please give us a call,” Saterfield said.