(Bloomberg) -- U.S. Vice President Mike Pence toured a facility at McAllen Border Patrol station where undocumented migrants were reportedly being kept in cages, sleeping on concrete and seemingly malnourished, and said “this is tough stuff.”

“This is the center -- the epicenter -- of the crisis on the southern border,” Pence said at a press conference following the visit. He reiterated the need to clamp down on illegal immigration.

Pence said he has pushed for more federal spending to deal with the situation on the U.S.-Mexico border. He rejected a claim by the Democrats that it was a “manufactured crisis,” and added that the overcrowding was so serious that a temporary facility had to be built.

“To stem this crisis of illegal immigration that’s coming out of Central America, we have to have Congress act,” Pence said.

Immigration has become an increasingly controversial issue during President Donald Trump’s administration, with his supporters demanding tighter border security and his opponents defending the rights of migrants. Trump has threatened to deport “millions” of undocumented immigrants as soon as next week.

In a subsequent press pool report, the Vice President’s Office said it had specifically instructed the Customs & Border Protection “to not clean up or sanitize the facility beyond what is routine so the American people could see how serious the crisis at our border is.”

To contact the reporter on this story: Natnicha Chuwiruch in Bangkok at nchuwiruch@bloomberg.net

To contact the editors responsible for this story: Shamim Adam at sadam2@bloomberg.net, Jasmine Ng, Alpana Sarma

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