They blew horns and whistles, and waved red and white union flags, outside the headquarters of Spain's industry ministry to demand that the government do more to keep the factory open and protect industrial jobs.
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Mr Teadoro Escorial deputy secretary of metalworkers union MGA-UGT told AFP “This is an absolutely tragic moment for our country. Without industry there is no future for our country.”
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ArcelorMittal's plant in Villaverde in the southern suburbs of Madrid made steel girders for construction before it went idle in October.ArclorMittal has offered to redeploy the 324 employees of the staff elsewhere in Spain and it left the possibility of reopening the site at a later date if demand picks up.
ArcelorMittal employs 11,000 people in Spain.