The Arizona rancher charged in the fatally shooting an unarmed migrant will not be retried for the crime.

George Alan Kelly, 75, was charged with second-degree murder and aggravated assault in the shooting death of Gabriel Cuen-Buitimea, 48, whose body was found on Kelly’s property near the U.S.-Mexico border, according to ABC News.

“Because of the unique circumstances and challenges surrounding this case, the Santa County Attorney’s office has decided not to seek a retrial,” said Deputy County Attorney Kimberly Hunley Monday.

When the announcement was made, Kelly appeared to become emotional.

Another hearing will be set to hear the defense’s request to dismiss the case with prejudice.

A judge declared a mistrial after jurors were unable to reach a verdict. He pleaded not guilty.

Kelly was accused of shooting his AK-47 at a group of migrants who were headed back to Mexico. 

Prosecutors Cuen-Buitimea, who lived just across the border in Nogales, Mexico, and was looking for work. 

The bullet was never recovered. 

Defense lawyers asserted that someone else could have shot Cuen-Buitimea.