UPDATE 1-U.S. steelworkers union petitions against large aluminum imports
April 18, 2016 at 12:42 PM EDT
NEW YORK, April 18 (Reuters) - The United Steelworkers (USW) said on Monday it has filed a complaint with U.S. regulators seeking to stem what it called a "flood" of aluminum imports that have damaged U.S. producers and threatened jobs.