In the long slog of the opioid drug crisis the U.S. is facing, every win counts.

U.S. Customs made its largest bust of fentanyl in its history at the Nogales port of entry on the border between Mexico and Arizona last Saturday. An estimated $3.5 million worth of the drug was seized, as well as $1.2 million worth of methamphetamine. That equals about 245 pounds of fentanyl, which is 100 times stronger than morphine and can kill with just a two ounce dose.

Fentanyl is a synthetic opioid, meaning that it is not actually made from opium poppies, and has become the leading cause of overdose in the U.S., killing tens of thousands of people every year. Opioid addiction has become a major crisis in the U.S., with addiction and overdose becoming ever increasingly common. Law enforcement and policy makers have struggled to keep up with the issue.

Here’s hoping for more major wins in the fight.