Minnehaha County Deputy Dies After Sioux Falls Shooting

Minnehaha County Sheriff’s Deputy Katherine Ann Frank died Monday, Oct. 12, after she was shot in the line of duty during a Friday night incident in southwest Sioux Falls, South Dakota, where authorities charged Brandon Oetken in connection with the shooting.

Frank, 26, served with the Minnehaha County Sheriff’s Office for just over two years after joining in June 2024, according to the sheriff’s office. She previously worked at the South Dakota State Penitentiary from September 2022.

Authorities said Oetken, 39, faces three counts of attempted first-degree murder on a law enforcement officer and three counts of aggravated assault on a law enforcement officer. The charges were announced by Minnehaha County State’s Attorney Daniel Haggar.

Minnehaha County Sheriff Mike Milstead and Sheriff-elect Josh Phillips addressed the loss in a statement about Frank’s service.

"Deputy Frank’s death is a significant loss to our agency and to the broader law enforcement community in and around Sioux Falls. She served the citizens of Minnehaha County with professionalism, humility and dedication," said Mike Milstead and Josh Phillips, Minnehaha County Sheriff and Sheriff-elect.

Phillips previously described the shooting response involving three deputies at the 2900 block of South Keyrell Drive in Sioux Falls.

"At approximately 8:02 p.m. (Saturday) shots were fired. One shot struck one of our deputies and the suspect. Medical aid was rendered to that deputy and the suspect on scene," said Josh Phillips, Minnehaha County Sheriff-elect.

A memorial was established at the Law Enforcement Center on 320 W. 4th Street in Sioux Falls, where community members gathered to honor Frank.

"Deputy Frank served with dignity and heart. Her service made a meaningful difference, and her impact will remain with us always," said Mike Milstead, Minnehaha County Sheriff.

The Sioux Falls Police Labor Council said the region had avoided a tragedy of this scale for generations and called for prosecution based on the evidence.

"For generations, the greater Sioux Falls area had been fortunate to be spared a line-of-duty tragedy of this magnitude," said the Sioux Falls Police Labor Council.

"As we honor her life and sacrifice, we also stand united in our call for justice. We urge the Minnehaha County State’s Attorney’s Office and all prosecuting authorities involved to pursue every criminal charge warranted by the evidence, to the fullest extent permitted by law," said the Sioux Falls Police Labor Council.

A fundraising page organized by the Minnehaha County Deputies Association said Frank is survived by her parents, boyfriend, five siblings and grandparents.

"Incredibly funny" and "someone who gets along with just about everybody" described Katherine Frank, according to her family through the fundraising page.

"She was deeply loved, and her loss is felt by so many," said the Minnehaha County Deputies Association fundraising page.

South Dakota officials also expressed condolences following Frank’s death.

"I’m praying for the family, friends, and colleagues of Deputy Katherine Frank. Her passing is tragic. I’m grateful for her service and join in honoring her sacrifice," said Dusty Johnson, U.S. Representative.

"The South Dakota law enforcement community suffered a great loss today. Kimberley and my thoughts and prayers are with Deputy Frank’s loved ones and colleagues during this extremely difficult time," said John Thune, Senate Majority Leader.

"My heart is heavy as we mourn the loss of Minnehaha County Sheriff’s Deputy Katherine Frank. Our law enforcement officers dedicate their lives to serving and protecting others, and their commitment and sacrifice should never be taken for granted. On behalf of the City of Sioux Falls, I extend my deepest condolences to Katherine’s family, friends, fellow deputies, and the entire Minnehaha County Sheriff’s Office.

Please join me in keeping her loved ones and our law enforcement family in your thoughts and prayers during this incredibly difficult time. Rest in peace, Katherine. Thank you for your service," said the City of Sioux Falls statement.

According to South Dakota Attorney General’s Office crime reports, more than 400 law enforcement officers in the state were assaulted while on duty each year during 2024 and 2025, the latest complete years available.