A father and son are charged in a string of construction thefts in Fond du Lac County. Fifty four year old, Ken Zangl and his 32 year old son Christopher made their initial Fond du Lac Court appearance this week on two counts of felony theft and two counts of misdemeanor theft. The pair is accused of stealing aluminum concrete forms from Cardinal Concrete in Fond du Lac. The stolen forms were later recovered at American Implement in Mount Calvary. An American Implement employee told investigators he purchased the aluminum rims from Ken Zangle. Charges are also being reviewed against a third man who may have been involved.