The governor of New Mexico invoked the state’s Riot Control Act on Friday as she sealed off all roads to nonessential traffic in the city of Gallup to help control a surging coronavirus outbreak in the former trading post city on the outskirts of the Navajo Nation.

Gov. Michelle Lujan Grisham also required that businesses close from 5 p.m. to 8 a.m. in the city of about 70,000 people along Interstate 40.

COVID-19 infection rates in Gallup and surrounding McKinley County make it one of the worst U.S. hotspots for the pandemic as patients overwhelm intensive care facilities.

Lujan Grisham said the virus has run amok in McKinley County and physical distancing is not being maintained among residents.

“A problem in one part of our state, with a virus this contagious, is a problem for our entire state,” she said.

State Police will assist local law enforcement and the National Guard will participate in a non-law enforcement capacity, the governor’s office said.

Federal health officials have linked the severity of the problem in Gallup to an early outbreak at a detox center that was followed by infections among homeless people.