The Larimer County, Colorado district attorney is looking into possible criminal charges after three officers were caught on video performing a violent arrest on an elderly woman with dementia.  The officers have resigned.

Her daughter told CBS News’ David Begnaud that she could not understand how this happened.

The woman, Karen Garner, was taking her four-times-a-day trip to Walmart in June to pick up a Pepsi, a Kit Kat candy, a t-shirt and wipes. 

Garner, who has dementia, left the store without paying. 

She returned the items after security caught her, but on her way home she was stopped by Loveland police.

“This is Mom’s jacket that she had on the day that it happened,” Gardner’s daughter, Allisa Swartz said. “And it’s got the blood on the back from where her hands were handcuffed.”

In the disturbing video, Garner is seen turning towards Loveland Officer Austin Hopp after being stopped two blocks from her home. She shrugs, unsure of what is happening. 

“Do you need to be arrested right now? Okay let’s stop. Come on,” Hopp says to Garner.

She tells him she is going home.

Seconds later, Garner’s face is in the dirt and her arms are cuffed behind her back. She pleads with the officer to let her go. 

Hopp refuses, picking up Garner before pinning her against the squad car.

“Oh if you try to kick me it’s going to be bad,” he says.

She cries out as another officer, Daria Jalali, comes around to assist. A popping noise can then be heard.

“Ow, you hurt me!” Garner says.

Garner collapses in pain before the officers throw her to the ground again.

At the time, the 80-pound 73-year-old woman was accused of stealing $13.88 worth of items from Walmart. Despite store security catching her, and her returning the items, Loveland officers pursued her.

“She was confused and scared. She didn’t understand what was going on,” Garner’s daughter said.

Swartz said she could not understand how the officer did not comprehend her mother just wanted to go home, and whether there were other factors at play.

“I was like, do you not understand? Because she is repeating over and over and just going home, I’m just going home. And it’s as if he wasn’t listening to her,” she said.

Garner had been taken to the local jail. Sitting in her cell, she repeatedly begs the officers to help her.

According to court papers, she sat for more than six hours without medical attention. She had suffered a dislocated shoulder, fractured arm and sprained wrist, as well as scrapes and bruises across her body. 

An audio engineer hired by Garner’s family was later able to enhance audio from the police station, where the officers could be heard mocking Garner.

Asked what the incident had done to her mother’s condition, Swartz said “It’s accelerated it. She’s scared, she’s anxious.”

Last month, Garner’s family filed a federal lawsuit against the city of Loveland and five officers for violating Garner’s civil rights. They claim Hopp used excessive force, and that Garner was left without necessary medical attention.

Loveland police policy dictates that when dealing with those suffering with mental illness, law enforcement personnel “should attempt to establish a sincere relationship with the individual.”

Mayor Jacki Marsh called the situation “sickening.” She wants the department to investigate its hiring practices.

“There obviously needs to be ongoing analysis of where people are in attitude,” Marsh said.

Swartz believes the officers should be prosecuted.

“I think they need to go to jail. Yes. They need to be held accountable,” she said.

The Larimer district attorney first saw the video of Garner’s arrest a month after the incident, the family’s attorney told CBS News, and he then dropped all charges against Garner. But he did not go after the officers.

Two police officers and a community service officer have since resigned from the force, because the video came out. One sergeant is on administrative leave.

The family attorney said he expects an announcement about potential charges this week. The Loveland Police Department and lawyers for the officers have not responded to CBS News.