Authorities found Koziol-Ellis dead in her Garden Crescent Place home at approximately 2:30 a.m. Saturday. They said the circumstances surrounding the woman's death seemed suspicious.
Neighbors say the 33-year old and her husband had just started moving into the Garden Crescent Court townhouse earlier in the week.
Salvador Santoyo, who lives next door to Koziol-Ellis, said he heard something strange as he was getting ready for bed about 1 a.m. Saturday morning, just hours before the gruesome discovery was made.
Authorities say the victim's husband found her lifeless body when he returned home around 2:30 a.m. and he immediately called 911.
He's cooperating with their investigation, according to police.
As of Saturday afternoon, investigators haven't determined if the killing of was targeted or random. No weapon was found at the scene. Police are seeking the public's help with the case.
The slaying is the first in Elgin in 2013.
The townhome association sent out an email alert warning residents to keep their doors locked, their porch lights on and to call police if they see anything suspicious.
Meanwhile residents like Joanne Johnson, who's lived in the neighborhood for 13 years, said she's afraid for herself and her teenaged daughter.
The Kane County coroner was set to perform an autopsy to determine exactly how the woman was killed. Those autopsy results were expected Sunday.
"I let my kids come out here and play all the time, and I still don't know what happened. Yeah, it's scary," said neighbor Pam Pouse. "I've simply seen her once, said hello to her, then I found out this happened."