OMAHA, Neb. (AP) — Two Omaha police officers will face assault charges in the death of a mentally ill man who was shocked with a stun gun a dozen times and repeatedly punched, even after he was on the ground, a Nebraska prosecutor said Wednesday.

Douglas County Attorney Don Kleine made the announcement while revealing police video  that captured the altercation officers Scotty Payne and Ryan McClarty had with 29-year-old Zachary Bearheels at an Omaha convenience store. Kleine said he wouldn't file more serious charges against the officers because a coroner could not directly link their actions to the Oklahoma man's death.

Police cruiser video shows Payne using a stun gun to shock Bearheels and McClarty punching Bearheels. Some of the blows came after Bearheels was on the ground and not resisting. Kleine said he would charge Payne with second-degree assault, a felony punishable by up to 20 years in prison. He said he's charging McClarty with third-degree assault, a misdemeanor punishable by up to one year in prison.

Bearheels, a Native American from Oklahoma, was lost in Omaha after being kicked off an interstate bus going from South Dakota to his home state, according to his family. Police were responding to a report of a man causing a disturbance who would not leave when they encountered Bearheels. Kleine said Bearheels "had committed no crimes."

Police have said Bearheels was acting erratically and fought officers' efforts to take him into custody. After the altercation, Bearheels was taken to a hospital, where he was pronounced dead.

Matthew Burns, an attorney for Payne, said his client is hoping that bail is set low enough that he can be released on Friday, when he's set to turn himself in to police.

"He feels awful," Burns said of Payne. "He's not a bad person. He didn't set out that day to go to work with the intent to hurt anyone."

Joseph Naatz, an attorney for McClarty, did not immediately return a message Wednesday seeking comment.

The officers, both of whom are black, were fired earlier this month based on the recommendation of police Chief Todd Schmaderer. Two other officers who witnessed the altercation were placed on administrative leave following Bearheels' death but do not face any charges.

Asked why he didn't charge Payne or McClarty with murder or manslaughter, Kleine said, "there's no evidence whatsoever that these officers intentionally killed Zachary Bearheels." Kleine also cited an autopsy report that said Bearheels died of "excited delirium," but couldn't say that the shocks or punching of Bearheels caused his death.

Bearheels' mother has told police and media in Omaha that her son was bipolar and schizophrenic. Relatives believe he had stopped taking his medication.

Nebraska law requires a grand jury investigation any time a person dies in police custody or while in the process of being arrested. Kleine said a grand jury has been set to convene on Sept. 26, but that the charges he's brought "likely make the grand jury process in this case moot."

An Omaha police union blasted Kleine's decision to charge the officers. The Omaha Police Officers' Association accused the Douglas County Attorney's Office of bowing to pressure and said prosecutors should have allowed a grand jury to determine whether charges were warranted.

The case prompted the city of Omaha to announce the forming of a Native American advisory board and training for police officers on indigenous culture.

Several members of the Native American community were present Wednesday for the announcement of charges, with most expressing outrage that Payne and McClarty aren't facing more serious charges and that no charges have been brought against two other officers on the scene.

April Gladfelter, 52, of Omaha, is a member of the Omaha Tribe and issued an emotional plea during the news conference for police to better learn how to interact with the mentally ill. Gladfelter said she has a son who is mentally ill, prompting her to contact Bearheels' mother after his death. The women now speak daily, she said.

"I fear for my son's life every day," she said, sobbing. "Are the police going to shoot him because he's talking to himself?”