Authorities have charged a Chickasaw County couple with first-degree murder and child endangerment following a two-month investigation into the death of their infant son.

Zachary Koehn, 28, and Cheyanne Harris, 20, were taken into custody on Wednesday (Oct. 25, 2017). Chickasaw County sheriff's officials were assisted by Charles City police and sheriff's officials in Fayette and Mitchell counties in locating and arresting the couple.

Koehn and Harris were the primary caregivers and biological parents of the 4-month-old child, authorities said.

According to information released by Chickasaw County sheriff's officials, deputies were called to the couple's apartment in Alta Vista on Aug. 30 on the report of an unresponsive child. When they arrived, authorities found the baby dead in his infant swing.

Sheriff's officials immediately launched a probe into the infant's death, with assistance from the Iowa Division of Criminal Investigation, state medical examiner's office and the Chickasaw County medical examiner.

No other information about the investigation was released.

Koehn and Harris are each being held on $100,000 bond. Both face a mandatory sentence of life in prison if they're convicted on the first-degree murder charge.