Sac City Police say an arrest has been made for the 2009 murder of Sac City resident Mark Koster. 54 year-old Orlando (FL) resident John David Greene is charged with 1st degree murder and is awaiting extradition back to Iowa. Koster went missing in 2009 and was declared dead in 2011. His remains were found in November of 2012 by the family that had purchased his home. The ongoing investigation into Koster's disappearance and death led officers to Green, who had lived with Koster for a short time in 2009. Sac City Police Chief Jon Thomsen says while interviewed, Green claimed responsibility for Koster's death and for hiding his body.