ORANGE CITY, Iowa (KCAU) – A man originally charged with second-degree murder in Sioux County has now had the charge changed to first-degree murder.

According to the Sioux County Sheriff’s Office, as part of their investigation into the murder of Grant Wilson, the charge filed against Gregg Winterfeld has been changed.

Officials said after a discussion with the Sioux County Attorney Office on May 22, they decided to amend the charge against Winterfeld, 70, of Spirit Lake, to first-degree murder. The original charge against Winterfeld was 2nd-degree murder.

On the evening of May 9, authorities received a report of a disturbance that involved a shooting inside of a residence on Dove Avenue, three miles northwest of Ireton. When deputies arrived, they found 58-year-old Wilson, of Cleghorn, dead inside of the house with an apparent gunshot wound.

The sheriff’s office said the case remains under investigation.