TUKWILA, Wash. - The mayor of the Seattle suburb of Tukwila has sent letters to NHL Commissioner Gary Bettman and NBA Commissioner Adam Silver expressing his support for a proposed new multipurpose arena that could house franchises for both leagues.

The city released documents pertaining to the proposed arena plan on Tuesday after public records requests.

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Mayor Jim Haggerton sent letters to Bettman and Silver last November expressing support for the proposal from The Russell Group, which includes prospective NHL owner Ray Bartoszek. Haggerton wrote the city has created a ''special opportunity district'' around a commuter rail station in the area where the arena would be built ''to facilitate greater intensities and uses.''

The documents also included rough sketches of where the arena would sit, next to Interstate 405, with potential parking structures and a hotel on the property.