(CNN) — More than one thousand female activists marched through Washington, DC, Thursday and flooded a Capitol Hill Senate office building to protest the Trump administration’s “zero-tolerance” immigration policy.

Democratic Sens. Ed Markey of Massachusetts, Mazie Hirono of Hawaii, Kirsten Gillibrand of New York and Richard Blumenthal of Connecticut visited the protesters to support their efforts.

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US Capitol Police arrested about 100 people at the protest in the Senate building so far. They are expecting to arrest “a couple hundred” on Thursday, they said.

The protestors are chanting “abolish ICE” amid other songs that are hard to hear within the building.

The activists sat on the floor of the Senate building with blankets to demand Congress act to end the Trump administration policies that criminalize and detain undocumented immigrants and separates their children from them.

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Congress is set to leave town for a week-long recess without passing any legislation to address the situation at the US border. On Wednesday, the House failed to pass legislation that would have address in part several high-profile immigration-related policies including border wall funding and an eventual pathway to citizenship for recipients of the Deferred Action for Childhood Arrivals program.

In an executive order last week, President Donald Trump said his administration was seeking more authority to detain families together until the end of their immigration proceedings.

The order instructs federal agencies — notably the Department of Defense — to prepare facilities to house the potentially thousands of families who will be detained.

This story is breaking and will be updated.

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