The alleged architect of hoaxes that drove up the share prices of Avon Products Inc and Rocky Mountain Chocolate Factory Inc has been arrested in Bulgaria and charged with eight U.S. criminal counts, federal prosecutors said on Thursday. Nedko Nedev, 38, a dual U.S.-Bulgarian citizen, was accused of having engineered bogus takeover bids for Avon and Rocky Mountain, and conducted insider trading ahead of a buyout offer for U.S. insurer Tower Group International Ltd. U.S. prosecutors said they plan to seek Nedev's extradition to the United States to face six counts of fraud and two counts of aggravated identity theft.