Gov. Michelle Lujan Grisham of New Mexico announced a 30-day ban on carrying firearms in public areas or state property in Albuquerque and its county, a move that she said was a necessary response to gun violence in the region but that critics denounced as unconstitutional.

The ban was issued on Friday as a declaration of a public health emergency, which Ms. Lujan Grisham said allowed the state to access different resources. The executive order, which covers Bernalillo County, prohibits open and concealed firearms on state property, public schools or public parks, with exceptions only for law enforcement and licensed security guards.

Residents with gun permits can still have weapons on private property. While traveling with a gun, a person must transport it in a way that makes the firearm inoperable — in a locked box or with a trigger lock, for example. Those who violate the order can be subject to fines up to $5,000.

Ms. Lujan Grisham, a Democrat, said she was spurred to action after several recent fatal shootings of children, including an 11-year-old boy who was killed outside a minor-league baseball stadium this week in Albuquerque.

At a news conference on Friday, she said that shootings have amounted to an epidemic and that the suspension allowed for a “cooling-off period” for the state to figure out the best way to address gun violence and public safety. She said she expected the suspension to be challenged in court and could not guarantee it would stand.

“I welcome the debate and the fight about making New Mexicans safer,” she said.

The New Mexico Shooting Sports Association, the official state association of the National Rifle Association, is in the process of filing a lawsuit against the ban, Anthony Segura, a spokesman for the organization, said.

Ms. Lujan Grisham “does not have the right” to override the federal and state Constitutions, he said.

Two New Mexico state representatives, Stefani Lord and John Block, both Republicans, called on Saturday for Ms. Lujan Grisham to be impeached, saying that she violated her oath to New Mexico and the nation.

Ms. Lujan Grisham said in a phone interview on Saturday that she remained confident in her decision.

“I have emergency powers,” she said. “Gun violence is an epidemic. Therefore, it’s an emergency.”

The executive order is statewide but affects only cities and counties that exceed certain levels of violent crime and gun-related emergency room visits, criteria that currently applies only to Bernalillo County, the seat of which is Albuquerque.

Harold Medina, chief of the Albuquerque Police, said in a statement that the governor had said that state law enforcement officers would be responsible for enforcing the order.

John Allen, Bernalillo County’s sheriff, said in a statement on Friday that the ban challenged the Constitution. He said he was wary of placing his deputies in positions where they could be vulnerable to civil liability, “as well as the potential risks posed by prohibiting law-abiding citizens from their constitutional right to self-defense.”

But he added that he was committed to fighting “the gun violence epidemic plaguing” the county.

The governor’s order also requires state regulators to inspect firearms dealers statewide every month to check their compliance with sale and storage laws. And the order directs the state’s Department of Health to gather demographic information — like age, race, ethnicity and gender — of gunshot victims, information on the brand and caliber of the firearm involved, and general circumstances leading to the injury.

Patrick Carter, co-director for the University of Michigan’s Institute for Firearm Injury Prevention, said there was evidence that fewer guns lead to less violence in an area. However, he said, there was not enough data or research to determine whether or not this ban would have an effect on preventing firearm injuries, which he said required “a comprehensive approach that blends policy with other types of interventions.”

Robert Leider, an assistant professor of law at George Mason University, said bans like this have been issued “when you have public disorders or other states of emergency, but most states of emergency usually involve something more acute.” He expressed skepticism that the ban would be upheld in court. “I’m not aware of any precedent for this just for general criminal wrongdoing,” he said.

In the news conference, Ms. Lujan Grisham said the ban would be lifted at the end of 30 days, if the gun violence epidemic was over. But she added, “I bet it’s not over in 30 days” and that the ban was likely to be modified.

“We’ll make adjustments, and I intend to make Albuquerque the safest place in America,” she said in the interview on Saturday. “It’s a tall order, and I am on it.”