DETROIT (Reuters) - The United Auto Workers (UAW) union is seeking a new election at a Mercedes-Benz plant in Alabama after losing a vote there last week, according to a petition filed on Friday with the National Labor Relations Board.

The union accused Mercedes of engaging "in a relentless anti-union campaign" including the firing of employees who were pro-union and holding frequent captive-audience meetings to spread anti-union views, according to the filing.

(Reporting By Nora Eckert; editing by Peter Henderson and Chris Reese)