The Washington Post has said that a massive drop in fentanyl seizures at the southern border is “mysterious” and that it is a “more complex” story than one would think after President Donald Trump has made it a point to crack down on border security as well as fentanyl trafficking into the US.

The outlet suggested that the Trump administration’s policies, such as threatening tariffs on China as well as Mexico to curb fentanyl, could have little to do with the drop in fentanyl, and claimed, “New data suggest a more complex story.”

This year, there has been a marked decrease in fentanyl seizures at the border, with a decrease also being shown before Trump took office.

A White House spokesman said that the drop in the seizures is “thanks to President Trump’s policies empowering law enforcement officials to dismantle drug trafficking networks,” but the Post countered this, saying “the decline started before Trump took office in January.”

The outlet went on to talk about the “Sinaloa cartel woes” happening in Mexico, where there have been two factions of the cartels attacking one another and Mexican President Claudia Sheinbaum has been targeting the cartel leaders, which would make the manufacturing of fentanyl more difficult. Trump has also worked with Sheinbaum to address the threats of the cartels early in his second term, deploying 10,000 troops to the border in February.

The authors went on to cite that there are signs that “many Mexico-based fentanyl cooks are having difficulty obtaining some key precursor chemicals” for fentanyl, according to the DEA. The outlet also speculated that drug traffickers could be better at evading authorities at the border or moving the illicit drugs into the US in different ways.

Drone flights, as well as an increased troop presence on the border from the Trump administration’s policies, may also serve as a deterrent for drug traffickers wanting to travel with fentanyl across the border.