Ivan Henk, who is accused of killing his 4 year-old son, is now also accused of assaulting an officer.
The incident took place Wednesday at the Cass County Jail, where Henk is being held while he awaits the murder trial of his son, Brendan Gonzalez.
Authorities say Henk pushed and grabbed a member of the jail staff. He is now being held in isolation.
Henk was charged with first degree murder in the disappearance of his son in January of 2003. Gonzalez's body has still not been recovered.