RRC Range Resources Corp

Northern Oil and Gas Inc. on Tuesday said it fired Chief Executive and co-founder Michael Reger, whose connection to a crude oil transport company is being investigated by federal authorities, and is reviewing options as it tries to recover from a slide in commodity prices.

The company named Chief Financial Officer Thomas Stoelk, 61 years old, its interim leader.

In a filing, the company said Mr. Reger received a Wells Notice from the Securities and Exchange Commission last Thursday in connection with a continuing investigation of 2012 trading patterns in the securities of Dakota Plains Holdings Inc.

The Wells Notice recommended the SEC take enforcement action against Mr. Reger—who was an initial investor in Dakota Plains in 2008—alleging violations of federal securities laws.

Northern Oil and Gas said it has never owned any interest in Dakota Plains and it doesn't believe it is the focus of any investigation by a governmental agency regarding the matter. It said it has fully cooperated with the SEC and will continue to do so.

The company said it doesn't believe Mr. Reger will be entitled to any severance payment. Mr. Reger has also been removed from the board, effective immediately.

Pointing to "the challenges of operating in a lower commodity-price environment," the company, which focuses on the Williston Basin in North Dakota and Montana, said the board is evaluating strategic alternatives.

Mr. Stoelk has been the company's finance chief since December 2011. Previously, he was with Superior Well Services Inc. and Great Lakes Energy Partners LLC.

Since joining Northern, Mr. Stoelk "has done an extraordinary job of overseeing the financial and administrative functions of the company and has successfully implemented our disciplined capital allocation protocols, which have benefited the company greatly over the past few years," said Chairman Richard Weber in prepared remarks.

Shares in the company, inactive premarket, have fallen 20% over the past 12 months to $3.98.

Write to Anne Steele at Anne.Steele@wsj.com

(END) Dow Jones Newswires

August 16, 2016 08:35 ET (12:35 GMT)

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