MEXICO CITY, (Reuters) – Mexican officials are speeding up the movement of thousands of migrants to Mexico’s southern border as they prepare for asylum seekers from the United States to return to Mexico.

Hundreds of migrants have crowded the Tapachula city in Chiapas in recent days, mostly from Central America and some from Cuba or Venezuela. They are heading to other countries, according to a Reuters witness on Monday and an activist.

Tapachula is a town near Guatemala’s border where many of these migrants waited for months to be granted asylum. Many migrants have fled violent, impoverished countries in hopes of seeking asylum in the United States.

The U.S. president Joe Biden announced Thursday that the administration would reinstate the Migrant Protection Protocols. This controversial Trump policy requires that asylum seekers wait in Mexico to resolve their case. Shelters at the border with Mexico fear that this could limit their ability.

Expect the return of Mexico’s first migrants from the revamped program this week.

According to a source in government, Tapachula saw 45 buses transport migrants from the city.

Luis Garcia Villagran, activist for migrants rights, stated that on Sunday 32 busloads of migrants left the city and on Monday 70.

He said, “They want to keep the northern border from being flooded now that MPP has started.” “That is why they’re moving them faster, and controlling the migration routes.

Mexico’s national immigration institute didn’t respond to our request for comment.

Unidentified Nicaraguan immigrant said that he felt relieved when he got on the bus to San Miguel de Allende, central Guanajuato.

He said, “I was only here for a couple of months, but I thank God that we’re going.”

An influx of large numbers of immigrants, particularly from Haiti, continued to gather in Tapachula while they waited for buses. Others slept outside Tapachula’s stadium which has been used as a processing facility by immigration officers.