Authorities in northern Mexico on Wednesday found about 70 pounds of fentanyl hidden inside boxes of sliced cactus, a quintessential Mexican food staple known as nopales.

Mexican law enforcement said they seized some 275,000 pills of the lethal drug in the border state of Sonora, on its way to Arizona, and that they arrested a 29-year-old man. The drugs were valued at about $6.5 million. Authorities found both pills and the drug in powder form.

The seizure took place at a military checkpoint on the Mexican highway connecting the northern states of Sinaloa and Sonora, where officers searched a trailer carrying packets of nopales.

It’s just the latest in a cat-and-mouse game between drug smugglers and authorities around the world, as traffickers find increasingly outlandish ways to sneak drugs into other countries. Packets of cocaine and fentanyl have been found tucked away in hair extensions, stowed inside car mufflers, baked into bread, and hidden inside avocados and bananas. Some organizations have used submarines to transport illicit drugs across international borders. 

The seizure also comes during a tense moment between Mexico and the United States, as Mexico scrambles to satisfy President Donald Trump’s demands to stop the flow of fentanyl and migrants north, which he has used to justify the 25% tariffs he put in place on Tuesday, though migration north and fentanyl overdoses had already sharply dipped before Trump took office. President Trump has made similar demands of Canada, but officials say very little fentanyl flows over that border. 

On Wednesday, Mr. Trump said that after negotiating with Mexican and Canadian authorities he would grant a one-month tariff exceptions to automakers, offsetting the brunt of the economic blow tariffs would dole out.