Thousands of fentanyl pills, hidden in candy boxes, were seized at the Los Angeles International Airport.

The Los Angeles County Sheriff's Office said the pills were seized on Wednesday morning when a person attempted to go through security with the drugs.

"It was discovered that inside the “Sweetarts”, “Skittles”, and “Whoppers” candy boxes were fentanyl pills and not candy," the sheriff's office said in a statement.

Authorities said they recovered approximately 12,000 fentanyl pills.

The sheriff's office said the suspect took off upon inspection of the candy boxes but was eventually detained.

As Halloween approaches, the sheriff's office is reminding parents to check their children's candy for anything suspicious.

"If you find anything in candy boxes that you believe might be narcotics, do not touch it and immediately notify your local law enforcement agency," the sheriff's office said.