Postponing Bridal Shower-Need Reply ASAP

What is the proper etiquette for postponing a bridal shower (invitations have already been sent) due to a death in the groom`s family. Is there a proper way to do this in writing or should it be by telephone. This was to be a shower for 75 to 100 people (very large family on the groom`s side), some member will have to attend a funeral service here and then travel up north for the burial, so should I do a handwritten note to each guest or telephone each guest that the shower will have to be postponed for a couple of weeks or so?
Please help. Invitations have already gone out and shower planned for in one week from the death of a very close family member of the groom. Thanks for your help. Just need to know what to say by telephone or by written announcement.



There has been a death in the groom`s family today and a bridal shower has already b