The candies were given out in food parcels distributed by anti-poverty charity Auckland City Mission. The Auckland City Mission

Pineapple candies dished out by a New Zealand charity have tested positive for "potentially lethal levels of methamphetamine," police said Wednesday, sparking an urgent race to remove them from the streets.

A child, a teenager and a charity worker have already been taken to a hospital after tasting the candies.

Although none are seriously ill, police have launched a criminal investigation and are trying to track down up to 400 other people who may have received the sweets.

"We need to round these up as quickly as we can," said Detective Inspector Glenn Baldwin, adding that 16 of the candies had been found so far.

Police suggested the drugs might have been packaged inside the distinctive yellow "Rinda" wrapping by traffickers or dealers to evade detection.

They are then believed to have been donated to anti-poverty charity, the Auckland City Mission, which inadvertently distributed them via a food bank.

"Drug importation is complex, and organized criminal groups use a range of measures and techniques to try and evade enforcement agencies, not only in New Zealand, but around the world," Baldwin said.

The child and teen who were brought to a hospital after tasting the sweets and spitting them out are both OK, Baldwin added.

The charity worker was also treated for symptoms consistent with ingesting methamphetamine but was later discharged.

The New Zealand Drug Foundation said a test sample of an innocuous-looking piece of white candy in a bright yellow wrapper indicated it contained methamphetamine.

Foundation spokeswoman Sarah Helm said the tested candy contained approximately three grams of meth - hundreds of times greater than the common dose taken by users.

"Swallowing that much methamphetamine is extremely dangerous and could result in death," Helm said.

She urged people who had received confectionaries from the Auckland charity not to consume them. "We don't know how widespread it is," she pointed out.

Malaysian sweet maker Rinda Food Industries said its branding had been "misused" and it did not "condone the use of any illegal drugs in our products."

"Our company is dedicated to ensuring that our products meet the highest safety and regulatory standards," it said.

The Auckland City Mission's Helen Robinson said the organization was "devastated" by the news.

Her organization believes as many as 400 people could have received the affected sweets in a food package.

Eight separate families had been affected so far, she said, including one instance in which a parent gave one of the candies to her child, who immediately spat it out.

Robinson said she had been told the potent contaminated candies tasted "acrid and revolting."

"You could have only a very small touch or lick of the substance and still be deeply affected," she warned.

A contaminated sweet was taken for testing when a person felt strange after starting to eat it and noticed a bitter taste.

Methamphetamine can cause chest pain, racing heart, seizures, delirium and loss of consciousness, the drug foundation warned.

Helm told Radio New Zealand it is common for drug smugglers to hide illegal narcotics in food form.

"We suspect somebody hasn't intentionally sought to poison children," she said.

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