Arizona rancher George Alan Kelly's murder charge downgraded to second-degree in shooting of Mexican migrant

The Arizona rancher accused of shooting and killing a Mexican national on his border property has had his first-degree murder charge downgraded to a second-degree one, a judge announced Friday.

Judge Emilio Velasquez spoke about the amended complaint during an evidentiary hearing for George Alan Kelly in Santa Cruz County Justice Court in Nogales, Arizona.

His attorney, Brenna Larkin, entered a not guilty plea.

"That's a significant change in the charge," she said. "Second-degree murder is, frankly, a more complicated theory of the case for both the state and the defense." 

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Kelly, 73, was released from custody this week after posting bond on Wednesday. 

Prosecutors allege Kelly opened fire with an AK-47 rifle on about eight unarmed migrants he encountered Jan. 30 on his ranch outside Nogales, striking the man who died in the back as he tried to flee. Two migrants in the group later told authorities that Kelly shot at them as well, but they were not hit and escaped over a fence back into Mexico. 

Prosecutors say the 48-year-old man who was killed lived just south of the border in Nogales, Mexico. The man is referenced in court documents only by his initials but has been identified by the Santa Cruz County Sheriff's Office as Gabriel Cuen-Buitimea.  

U.S. court records show Cuen-Buitimea was convicted of illegal entry and deported back to Mexico several times, most recently in 2016, according to The Associated Press. 

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Kelly also faces two counts of aggravated assault against the two migrants who came forward and said they would testify. Prosecutors have said even though the men were not hit, one said they "felt like they were being hunted." 

Kelly’s attorney has said Kelly did not shoot and kill the man, but Kelly acknowledges that earlier in the day he fired warning shots above the heads of smugglers carrying AK-47 rifles and backpacks on his property.

Larkin told the courtroom Wednesday that there's a "very large incentive structure for people to come forward and to have claimed to have been witnesses," noting the expectation of immigration benefits, as well as "pressure from traffickers who have an interest in blaming this event on Mr. Kelly."

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The Associated Press contributed to this report.