President Donald Trump urged Mexico on Monday to send the growing flow of migrants from South America back to their countries of origin.

“Mexico should move the flag-waving Migrants, many of whom are stone cold criminals, back to their countries,” Trump wrote on Twitter. “Do it by plane, do it by bus, do it any way you want, but they are NOT coming into the U.S.A.”

More than a hundred migrants who tried to rush through the border were turned back as American agents fired tear gas at the approaching crowds.

Currently, 5,000 migrants are in a camp in Tijuana while the Trump administration is urging the Mexican government to keep them from the border. Thousands of additional migrants are also expected to arrive in Tijuana.

“Would be very SMART if Mexico would stop the Caravans long before they get to our Southern Border,” Trump wrote on Twitter on Sunday.

Trump is reportedly working on a deal with the Mexican government to keep migrants in Mexico while they await asylum claims, instead of allowing into the United States. The incoming Mexican administration, however, denied that they are putting that kind of policy in place.

The president is putting more pressure on Mexico, warning that he might close the southern border “permanently” if necessary.

He also demanded that Congress fund his promised wall proposed for the border.

Funding for the Department of Homeland Security expires on December 7:

Mexico should move the flag waving Migrants, many of whom are stone cold criminals, back to their countries. Do it by plane, do it by bus, do it anyway you want, but they are NOT coming into the U.S.A. We will close the Border permanently if need be. Congress, fund the WALL! — Donald J. Trump (@realDonaldTrump) November 26, 2018