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                                                                    EXHIBIT 99.a



                               [ONEOK LETTERHEAD]

[ONEOK LOGO]  FINANCIAL NEWS
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                            ONEOK CLOSES $285 MILLION
                        KOCH MIDSTREAM ASSET ACQUISITION

         TULSA, Oklahoma - ONEOK, Inc. (NYSE:OKE), announced today the closing
of the acquisition of the Oklahoma midstream natural gas gathering and
processing assets of Koch Midstream Enterprises for $285 million in cash. The
assets include eight natural gas processing plants and approximately 3,250 miles
of gathering pipeline connected to 1,460 gas wells located in Oklahoma.

         David Kyle, president and chief operating officer of ONEOK, said, "We
are very pleased to close this important acquisition. It helps ONEOK continue
its strategic objective of maximizing values in all its nonregulated assets
including natural gas reserves, processing plants, gathering, transportation and
marketing operations.

         "Total capacity of these plants is 515 million cubic feet per day.
Current throughput is approximately 285 million cubic feet per day, which
represents a great opportunity for us to focus on connecting more supply by
optimizing the system and offering prompt and efficient services to producers.
The plants are producing 19,000 barrels of natural gas liquids per day at
current throughput levels.

         "We look forward to new opportunities of providing midstream services
to the Oklahoma producing community. We have been an active participant in the
state's natural gas industry since before statehood and we are pleased to
increase our investment in this business."

         ONEOK, Inc., is an integrated natural gas company involved in
production, processing, gathering, storage and transmission. The company is also
the largest natural gas distributor in Kansas and Oklahoma operating as Oklahoma
Natural Gas Company and Kansas Gas Service Company serving 1.4 million
customers.

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STATEMENTS CONTAINED IN THIS RELEASE THAT INCLUDE COMPANY EXPECTATIONS OR
PREDICTIONS OF THE FUTURE ARE FORWARD-LOOKING STATEMENTS INTENDED TO BE COVERED
BY THE SAFE HARBOR PROVISIONS OF THE SECURITIES ACT OF 1933 AND THE SECURITIES
EXCHANGE ACT OF 1934. IT IS IMPORTANT TO NOTE THAT THE ACTUAL RESULTS OF COMPANY
EARNINGS COULD DIFFER MATERIALLY FROM THOSE PROJECTED IN SUCH FORWARD-LOOKING
STATEMENTS. INFORMATION IS AVAILABLE ON THE INTERNET WORLD WIDE WEB AT
http://www.oneok.com.
