Navajo Nation Officer Houston James Largo, 27, died after being critically wounded near the small town of Prewitt, said Frank A. Fisher, an FBI spokesman in Albuquerque. The agency, which is investigating along with the tribe, said a suspect was in custody, but no other details were released.
Largo was flown to the University of New Mexico Hospital, where Navajo Nation President Russell Begaye said he went to give condolences to the officer's family.
"Our nation mourns for you as does the country," Begaye said in a statement. "Our officer's lives are precious. They are the ones who stand guard over our nation and protect us."
He said earlier Sunday that tribal officers are well-trained but face danger.
"Our officers put themselves in highly volatile situations every day in addressing domestic violence situations," Begaye said.
He said the tribe recently upgraded equipment and protective devices for its police department.
Begaye says Largo was from Thoreau, New Mexico, and had served with the department for 4 years. The FBI said Largo had five years of service. The Associated Press could not immediately reconcile the two numbers.
The tribal president said he appreciated a call from New Mexico Gov. Susana Martinez and her offer to help after the shooting.
"This sad news reinforces the dangers our police officers face every day - so we and our families don't have to," Martinez said in a statement. "I'm confident the monster who took this brave officer from us will face the full measure of justice."
New Mexico State Police and the McKinley County Sheriff's Office also were assisting with the investigation.
Begaye and Vice President Jonathan Nez called for support and respect of officers from the Navajo Nation, which covers 27,425 square miles in portions of Arizona, Utah and New Mexico.
"Our Navajo Nation police officers risk their lives every day to protect our communities," Nez said in the statement. "Officer Largo is a great example of an officer who paid the ultimate sacrifice to protect the life of another."
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