PORTLAND — Midcoast businessman Reade Brower has reached a deal to purchase MaineToday Media, the newspaper group that owns the Portland Press Herald, the Maine Sunday Telegram, the Kennebec Journal and the Morning Sentinel.

A memo sent to Maine Today Media staff late Tuesday confirmed financier S. Donald Sussman, husband of Democratic U.S. Rep. Chellie Pingree, agreed to sell the paper. He paid $3.3 million for a 75 percent stake in the company in March 2012 and, according to the memo, invested $13 million in the newspaper group since that purchase.

The memo did not disclose a sale price but said the deal will help the newspaper group overcome two major challenges: debt inherited from the paper’s previous owners and the cost of printing the paper on aging presses.

“The sale resolves the balance sheet problems as all proceeds from the sale are going to pay company debt, with the bank receiving the vast majority of the proceeds to retire its loan, and addresses the production challenge by putting the company in the hands of an experienced commercial printer and newspaper operator,” the statement to employees said.

The statement said Chris Miles, former publisher of The Times Record and current partner with Brower in the Brunswick-based Alliance Press, also will be a partner in the deal. Alliance Press is a commercial printing operation based in Brunswick. It does some contract work for the Bangor Daily News.

Brower plans to purchase the newspaper group through a new company called MTM Acquisition, which became registered with the Maine secretary of state on April 13.

Brower, a Rockland resident, also owns The Free Press and The Courier-Gazette in Rockland, The Camden Herald and The Republican Journal in Belfast.

Maine Today also operates the Bath-based Coastal Journal and has about 400 employees. The deal still requires union approval and is scheduled to close June 1, the internal statement said.

“Over the next month, we will share details of the transition plan,” the company statement said. “One of the company’s first tasks after completing the transition will be to work with Chris (Miles) to map out a plan for resolving our long-term production strategy.”