Service of citation or other process on any political subdivision, public corporation, or state, parochial or municipal board or commission is made at its office by personal service upon the chief executive officer thereof, or in his absence upon any employee thereof of suitable age and discretion. A public officer, sued as such, may be served at his office either personally, or in his absence, by service upon any of his employees of suitable age and discretion.

If the political entity or public officer has no established office, then service may be made at any place where the chief executive officer of the political entity or the public officer to be served may be found.