Friday’s rampage is believed to be the worst mass killing in Virginia Beach’s history. Prior to this week, a shooting on June 30, 1994, at the Witchduck Inn held that distinction: Four people — the business owner, two employees and a patron — were shot to death at the restaurant. It also came on the heels of a shooting in Chesapeake’s Holly Cove community over Memorial Day weekend that left one dead and nine others injured.