WASHINGTON – A federal employee union sued the Trump administration Monday over the government shutdown, claiming it is illegal for agencies to force employees to work without pay.

The American Federation of Government Employees announced the lawsuit as the partial government shutdown began a second week. Hundreds of thousands of workers have been furloughed or are on the job without pay during the shutdown.

“Our members put their lives on the line to keep our country safe,” said J. David Cox Sr., the union’s national president. “Requiring them to work without pay is nothing short of inhumane.”

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The partial shutdown began on Dec. 22 after President Donald Trump and congressional Democrats failed to come to an agreement over White House demands for increased border security money. Trump has called for as much as $5 billion in additional funding to pay for a wall along the U.S.-Mexico border.

AFGE, one of the largest federal employee unions, sued the government on similar grounds following the 16-day shutdown in 2013. A U.S. Court of Federal Claims judge ruled in 2017 that some 25,000 employees who were required to work without pay during that period were entitled to double pay as damages.