YUMA, Ariz. (NewsNation) — U.S. Customs and Border Protection officials seized more than 2,100 pounds of fentanyl in July, compared to 702 pounds seized at the nation’s borders in June.

Arizona Gov. Doug Ducey said over the course of 48 hours last week, the Arizona Department of Public Safety seized 80 pounds of suspected fentanyl — which holds a street value of about $3.6 million.

In the Tucson sector, agents worked Tuesday night with the Cochise County Sheriff’s Office to stop a human and drug smuggling attempt — a U.S. citizen attempted to transport three migrants, and an undisclosed amount of fentanyl was seized from the vehicle.

According to the U.S. Drug Enforcement Administration, two milligrams of fentanyl is enough to kill one person.

CBP data also showed that in July there were 146 fentanyl seizure events, while June had 113.

All of this comes as Ducey is working to use shipping containers to close a 1,000-foot gap in the border wall near Yuma.

Officials with Ducey’s office say they were acting to stop migrants after repeated, unfulfilled promises from the Biden administration to close the gap.

Federal officials have not commented on the state’s actions, which come without explicit permission on federal land. State contractors began moving and stacking 60-foot-long, 9-foot-tall shipping containers early Friday. Two other 1,000-foot gaps also will be closed off. The containers will be topped with 4 feet of razor wire.