Sioux Falls Police are looking for a killer Monday night.
The victim was found in her home on the 700 block of South Garfield Avenue, where she lived alone.
That's near Garfield Elementary School.
Police say 56-year-old Kari Kirkegaard was discovered Sunday evening, but it was not until an autopsy Monday, that her death was ruled a homicide.
Neighbors said it is normally a safe neighborhood.
Police were on the scene since Sunday afternoon and were still there Monday evening.
The neighbor KSFY News talked to said the situation is nerve-wracking, but the police presence is comforting.
Police found Kari Kirkegaard dead inside her home Sunday evening.
There was no obvious cause of death so they did an autopsy Monday morning and now say she was killed.
"It's sad to hear it makes you feel a little bit nervous about the situation but our neighborhood is very peaceful. To see a situation with this happened but it is very sad that this is taking place. Now you want to know all your neighbors so if anything happens you're all aware," said neighbor Kari Smith.
Police said Kirkegaard's bed sheets are missing.
They are asking neighbors to check their garbage for anything suspicious.
"We had a detective stop by earlier and I believe they went to check around and to check out the garage to make sure nothing was going on with that. But definitely going to keep my eye out for anything," Smith said.
One of Kirkegaard's friends stopped by to see for herself what was going on.
She did not want to give her name, but said they have been close friends for thirty years, "She was obviously a very loving and caring person, she had lots of friends and she would just mind her own business and stay at home. She enjoyed shows like the voice and movies and she'd record those."
She added Kirkegaard was a fighter. She had been breast cancer free for two years.
She cannot believe someone would do this to her friend.
"I just can't believe it. She had a lot of hopes in the summer to sit out back and to paint the house."
This homicide remains under investigation.
If you saw Kari Kirkegaard in the past week or find anything unusual in your garbage, police want to hear from you.