A Pennsylvania man was arrested Thursday and charged with the murder of a missing co-worker after investigators found the woman's body on his property, police said.
Authorities believe she was kidnapped and brought to Monroe County.
Investigators say Horvath and Grim had the same work schedule at the Allen Organ Company in Lehigh Valley.
On the day of Grim's disappearance, Horvath was late for work and claimed he had a flat tire. Authorities continued to question Horvath over the past three years as a person of interest.
In 2014, a blood sample found at Grim's home matched his DNA.
Then, over the past couple of weeks, authorities searched the inside and outside of Horvath's home on Woodhaven Drive in Ross Township. Tests showed that several bones belonging to Holly Grim were buried in the backyard.
"At this point, I would just like to offer my condolences to the Grim family, especially Jeanette her mother," said Lt. Joseph Sokolowski, of the Pennsylvania State Police. "I know it's not the outcome she was hoping (for), however I hope she finds some solace and relief from the daily anguish I am sure she suffered from the unbeknown."
Investigators are still trying to determine a motive and testing is still being done to determine how Grim was killed.
Police say numerous tapes and DVDs relating to murder, sexual deviance, and "hunting humans" were found in Horvath's home.
Michael Horvath is being held at the Monroe County jail. A preliminary hearing is scheduled for Oct. 24.