Marijuana-infused candy seized in Prince George’s County. (Courtesy of Prince George's County Police)

The sweets look innocent.

A Monkey Bar with “two kinds of chocolate, coconut oil, toasted walnuts, and real bananas.”

Or the Blueberry Bliss, a treat with “white chocolate, flax crispies, and real blueberries.”

But there is one special ingredient in these candy bars and other treats Prince George’s County police seized in Maryland two days ago that authorities are warning parents about in light of Halloween: marijuana.

On Friday morning, as kids across Prince George’s County were eagerly awaiting their chance to don their Elsa and Spider-­Man costumes for a night of trick-or-treating, officials there announced that they had seized boxes of marijuana-infused candy from Colorado .

With the legalization of medical marijuana in the District, Maryland and nearly two dozen states and of recreational marijuana use in Colorado and Washington state, edible cannabis products are a burgeoning industry across the United States. But the seizure of marijuana-infused taffy and chocolates in Maryland reflects a new challenge law enforcement must contend with in states where such products are illegal.

Prince George’s police officials say they don’t think that the candy was intended to wind up in kids’ trick-or-treat bags, but authorities wanted to warn parents.

“It’s relatively innocuous if you look at it,” said Capt. Chuck Hamby, assistant commander of the police department’s narcotic enforcement division. “For the safety of the community and the holiday season, we wanted to get it out right away.”

The six types of candy that police intercepted, mostly chocolate bars and taffy, boast bright labels that could wind up in the hands of kids eager to gobble down goodies without understanding the labels, authorities said. Along with the Monkey Bars and Blueberry Bliss, there were Mad Mints, Karma Kandy and other flavored chocolates. Many of the products say: “Warning: Extremely potent. Do not eat all at once” and “Keep away from children.”

Hamby said the candy is legally made and sold in Colorado and that it is the first time the department has seen the items in this area.

The narcotics enforcement division seized the candy two days ago during “normal duty,” but Hamby would not say where, citing the ongoing investigation. The candy came from four manufacturers, and county police field-tested the products after the boxes were seized, confirming that they contained THC, the element in marijuana that causes people to get high, Hamby said.

Prince George’s officers are working with the Metro Area Drug Task Force, headed by Maryland State Police, to investigate the candy seizures, said Lt. William Alexander, a county police spokesman. The Drug Enforcement Administration was alerted because the probe crosses state lines.

Hamby would not provide a street value for the confiscated candy but said that because the products are new to the area, “the price would be pretty high.”

Marijuana-laced edibles are an issue public safety officials in Colorado have been dealing with for quite some time. Denver police spokesman Ron Hackett said law enforcement officials in Colorado have made sure to warn parents about edible cannabis products getting into children’s hands.

“Basically, the first thing we did when marijuana became legal is we put things out showing the difference between real candy” and edibles, Hackett said. “We ask parents to treat it like any other kind of medicine.”

Hackett said he was not aware of instances in Denver of children having overdosed on marijuana-infused candy, but many adults have abused the product by eating more than the recommended dosage. “They get really sick,” Hackett said of someone who consumes too much. “They think they’re having a heart attack.”

Hamby said it’s unlikely that a child who gets ahold of the candy will die, but if parents find that kids have consumed some of it, they should go to a medical professional.

Oak Peak is a “budtender” at the Giving Tree of Denver, a marijuana dispensary that sells such edibles as Karma Kandy.

Peak said he agrees that police should warn parents about keeping the edibles away from children, something he also stresses to his customers. But Peak questions whether many would be willing to drop hash-infused candies into kids’ goodie bags.

“Everybody is a little nervous because today is Halloween,” Peak said. “But I ask this question all the time: If someone spends roughly $20 per edible, would they give that away free, let alone to a child?”

Hamby asked parents to be on the lookout and check for labels that indicate that the products contain THC, because anything can happen: “Since it’s the first time we’ve seen it here, better safe than sorry.”