A New Hampshire hotel developer has bought a majority stake in two high-end Portland hotels.

XSS Hotels, based in Hooksett, said Wednesday that it acquired a controlling interest in the Portland Harbor Hotel, on Fore Street in the Old Port, and The Inn at Diamond Cove, on Great Diamond Island in Casco Bay.

The deal also includes restaurants at both hotels and a marina on the island.

Bateman Partners, the hotels’ original Portland developer, will keep a minority stake in the properties.

The affiliated management company for XSS, Colwin Hotels, will take over operations at the two properties, the company said in a statement.

Most of the hotels owned by XSS are in New Hampshire and Massachusetts. This purchase marks its first move into the Maine lodging market.