Should the FBI publicly announce investigations before they begin?

Unless you have been living in a cave for the last 24 hours you probably have heard that the FBI is opening a new investigation into Hillary Clinton’s emails that were allegedly found on a device used by Anthony Weiner. What makes this unique is that the election is less than 2 weeks away and also that the FBI typically doesn’t announce when they open and close cases. FBI Director James Comey stated that because of the election, he needed to inform lawmakers and hence the public about the case. Comey went on to add that there is no evidence at this point of wrong doing and that they are investigating. With that said “Should the FBI publicly announce investigations before they begin?”