Tens of thousands of migrants, many of them Haitians who had been living in South America, have arrived in recent weeks in Mexico hoping to enter the United States.
Mexican authorities have arrested more than 147,000 undocumented migrants already this year -- three times more than in the same period of 2020, according to the National Migration Institute.
Under the Remain in Mexico program, tens of thousands of non-Mexican asylum seekers were sent back over the border pending the outcome of their applications.
US authorities began on Friday deporting some migrant families on flights to Central America as part of an expedited system to remove people who arrived without authorization via Mexico.