The parents of Micah Johnson, the 25-year-old man authorities say killed five Dallas police officers and injured several others last week, are speaking out for the first time.

Johnson, an Army Reserve veteran, had been excited to join the military and was passionate about protecting his country, Johnson’s parents said in an interview with The Blaze set to air this week. But over his six years of service, including a deployment to Afghanistan, Johnson became a “hermit,” the Johnsons said.

“The military was not what Micah thought it would be,” said his mother, Delphine Johnson. “He was very disappointed, very disappointed, but it may be that the ideal that he thought of our government, of what he thought the military represented, it just didn’t live up to his expectation.”

Johnson opened fire on police officers during an otherwise peaceful protest over the police killings of Philando Castile in Minnesota, and Alton Sterling in Louisiana. Police killed Johnson with a bomb-carrying robot, ending a standoff. They said he acted alone and had plans for a larger attack.

Johnson was discharged from the military after being accused of sexual harassment. According to his family, he became interested in his black heritage after leaving the military, but never showed animosity toward people of other races.

“I don’t know what to say to anybody to make anything better. I didn’t see it coming,” said Johnson’s father, James. “I love my son with all my heart, I hate what he did.”

Watch a clip of the interview above.

Dallas Police Chief David Brown said Sunday that Johnson left cryptic messages in his own blood inside the building where he was killed Thursday evening. Police said they found rifles, bomb materials and a journal of “combat tactics” in his home.

“We’re convinced that this suspect had other plans and thought that what he was doing was righteous and believed that he was going to target law enforcement ― make us pay for what he sees as law enforcement’s efforts to punish people of color,” Brown said in an interview with CNN.