(CNN) Michigan authorities have seized records from every Catholic diocese in the state as part of an investigation into possible sexual abuse by clergy, the dioceses said in separate statements released Wednesday.

The Archdiocese of Detroit, and dioceses in Gaylord, Grand Rapids, Kalamazoo, Lansing, Marquette and Saginaw said their offices were served search warrants Wednesday morning from Attorney General Bill Schuette.

Schuette's office announced last month that it would be looking into possible sexual abuse by priests in the state's seven dioceses.

CNN has reached out to Schuette's office for comment.

A post on the attorney general's website says the investigation will be "independent, thorough, transparent and prompt" and will "find out who knew what, and when."