UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) September 20, 2001 MDU Resources Group, Inc. (Exact name of registrant as specified in its charter) Delaware 1-3480 41-0423660 (State of other jurisdiction (Commission (I.R.S. Employer of incorporation) File Number) Indentification No.) Schuchart Building 918 East Divide Avenue P.O. Box 5650 Bismarck, North Dakota 58506-5650 (Address of principal executive offices) (Zip Code) Registrant's telephone number, including area code (701) 222-7900 Item 5. Other Events. Incorporated by reference is a press release issued by MDU Resources Group, Inc. on September 20, 2001, attached as Exhibit 99. Item 7. Financial Statements and Exhibits. (c) Exhibits. Exhibit 99 - Press release issued September 20, 2001 regarding natural gas price volatility. SIGNATURE Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. MDU RESOURCES GROUP, INC. Date: September 21, 2001 By: /s/ Vernon A. Raile Vernon A. Raile Vice President, Controller and Chief Accounting Officer EXHIBIT INDEX Exhibit Number Description of Exhibit 99 Press release issued September 20, 2001 regarding natural gas price volatility.