DALLAS (CBSDFW.COM/AP) – A grand jury has declined to bring charges against the Dallas police officers who used a bomb-carrying robot to kill a sniper who had gunned down five other police officers during a downtown rally, prosecutors announced Wednesday.

The Dallas County District Attorney’s office said in a release that investigators presented their findings to a grand jury more than a year after the July 7, 2016 attack by Micah Johnson, a 25-year-old Army reservist who investigators said was upset by recent shootings of black men by police.

Prosecutor Faith Johnson, who has no relation to the gunman, noted that all police shootings are required to be examined by a grand jury. “Our thoughts and prayers continue to be with the families of those who lost their lives that night, the officers who were injured, and all of the men and women who courageously put themselves into harm’s way, all in an effort to protect our community,” she wrote.

Faith Johnson said that her office had returned all investigative materials to the Dallas Police Department.

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Police in Dallas work near the scene where 12 officers were shot and five died on July 8, 2016 in Dallas, Texas. (credit: Ron Jenkins/Getty Images)

A police spokeswoman issued a statement as well. “Our community will never forget the tragedy of July 7, 2016 and the impact it has had on all of us,” the statement read. “We are pleased with the outcome of this investigation and we hope to continue to move forward with the healing process.”

The decision appears to conclude the investigation, which began shortly after gunman Micah Johnson fatally shot four Dallas police officers and a transit officer as a rally protesting previous police shootings in other cities was ending. Micah Johnson eventually holed up in a community college building, when police officers used a bomb-carrying robot to end an hours-long standoff.

Micah Johnson died from his injuries, but little more is known about the decision to use the robot, a first for a U.S. law enforcement agency. Police Chief David Brown, who has since retired, wrote about his role in the decision in his autobiography, but he said during interviews about the book that he purposefully did not look at the investigative file while writing his account.

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Micah Johnson

The Associated Press along with other media outlets filed multiple Freedom of Information requests regarding the shooting, including for autopsies, ballistic reports, the 911 calls, surveillance video, transcripts of the negotiations with Johnson and an inventory of what was seized from his home. Those requests were denied citing an ongoing investigation.

During the investigation, officers gathered about 200 shell casings, including 118 from the 44-foot El Centro College hallway that separated police negotiators and the spot where Johnson holed up, Assistant Chief Randal Blankenbaker said on the anniversary of the attack. He said investigators reviewed thousands of hours of camera footage.

Michael Mata, president of the Dallas Police Association, the city’s largest police union, said the shooting has had a lasting effect on the city’s officers. “Obviously, it was a long and stressful time and situation for the officers involved, who did their duty in protecting the public and the other officers at the scene. It’s unfortunate that there was a loss of life but the officers did their duty and were the upmost professionals,” he said. “We’re happy that the officers are able to move on with their careers and we’re happy that the justice system worked out as it is designed to do.”

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