Knife River Corporation Adds Montana-based D'Agostino Companies.

Business Editors

BISMARCK, N.D.--(BUSINESS WIRE)--April 4, 2000

MDU Resources Group, Inc. (NYSE:MDU) announced that it acquired the Montana corporations of D'Agostino Companies which provide concrete ready-mix and related services in the Bozeman, Montana area. The acquisition is expected to be accretive to MDU Resources' earnings. Financial details of the transaction were not disclosed.

D'Agostino Companies are headquartered in Belgrade, Montana, and serve customers within a 40-mile radius. The market area includes Bozeman, which is one of the fastest growing cities in the state of Montana. Sales for the year ended December 31, 1999, were approximately $8 million. The D'Agostino Companies included in the purchase are D'Agostino Concrete, Inc., a Belgrade, Montana, ready-mix supplier; Chamber Dawgs, Inc., a Livingston, Montana, ready-mix supplier; D'Agostino Masonry Supply, Inc., a retail supplier of masonry products including stone, rock, rebar and foam blocks; and D'Agostino Concrete Pumping, Inc., a concrete pumping company. The companies serve residential, commercial, contractor and government customers. D'Agostino operations will be combined and incorporated with those of the JTL Group, Inc. which became part of the MDU Resources' construction materials and mining subsidiary of Knife River Corporation (KRC) in 1999. Current D'Agostino Companies' management and employees will become part of the new company.

"This transaction allows KRC to add a concrete ready-mix operation to its operations in the Bozeman and Livingston areas as well as to extend service to other nearby areas," stated Terry D. Hildestad, president and chief executive officer of KRC. "The D'Agostino Companies are a natural extension of our construction materials operations in Montana. Besides complementing our existing lines of business, this acquisition also gives us the opportunity to take advantage of synergies between the D'Agostino Companies and JTL Group."

The information in this release includes certain forward-looking statements, including statements concerning accretive earnings and synergies, within the meaning of Section 21E of the Securities Exchange Act of 1934. Although the company believes that its expectations are based on reasonable assumptions, actual results may differ materially. Important factors that could cause actual results to differ materially from those in the forward-looking statements include the effects of competition and the ability to effectively integrate the operations of the acquired companies. For a discussion of other important factors refer to the company's documents and reports that are available from the Securities and Exchange Commission, including the report filed on Form 10-K for the fiscal year ended December 31, 1999.

MDU Resources Group, Inc. provides energy, value-added natural resource products and related services that are essential to our country's energy, transportation and communication infrastructure. MDU Resources includes an electric and natural gas utility, a natural gas pipeline, utility services, oil and natural gas production, construction materials and mining, and energy services. For more information about MDU Resources, see the company's web site at http://www.mdu.com or contact the investor relations department at [e-mail].