A report published by Amnesty International found that the US and Mexico returned tens of thousands of migrant children.
Mexican security and migration officials have blocked the passage of a new migrant caravan, detaining several people, as the government moved to break up the group just a day after it set off from southern Mexico for the United States.
At about 5am local time (10:00 GMT) on Sunday, members of Mexico’s National Guard and the National Institute of Migration (INM) began surrounding the migrants on the edge of the southern town of Huixtla, prompting some of them to flee, a witness told the Reuters news agency.
In the ensuing commotion, some parents in the caravan made up largely of Central Americans, Haitians and some Venezuelans were separated from their children as the officials sought to intercept people who ran for the banks of the River Huixtla.
The operation to stop the caravan of about 400 people comes a few days after officials dispersed another large group and followed comments by Mexican President Andres Manuel Lopez Obrador that he wanted undocumented migrants to stay in southern Mexico.
Lopez Obrador also urged the US government to help the people find work, speaking ahead of a high-level meeting of US and Mexican officials on Thursday that is due to address economic matters and also expected to encompass migration.
US President Joe Biden came into office promising to take a more humane approach to immigration and roll back some of his predecessor Donald Trump’s most hardline policies.
But the Democratic Party leader has kept in place a Trump-era order known as Title 42 that allows US officials to immediately turn back most asylum seekers who arrive at the country’s borders to stem the potential spread of COVID-19.
Biden administration officials also have exerted diplomatic pressure on Mexico, as well as Central American governments, to do more to stem high numbers of migrants and asylum seekers taking dangerous journeys north towards the US.
Thousands of largely Central American asylum seekers have tried to reach the US in recent months, fuelled largely by poverty, unemployment, gang violence and the devastation of recent storms.
US immigration advocates slammed Biden last month for what they described as “cruel, unlawful and ineffective” measures aimed at stemming arrivals.
On September 1, a group of US public health experts also urged the administration to rescind the “discriminatory and unjustifiable” Title 42 order and instead “adopt measures that are based on sound science and public health practice, and that comply with US law and treaty obligations towards refugees and asylum-seekers”.
As had occurred with the previous caravan in Mexico, some migrants accused Mexican security forces of using excessive force during their intervention.
Maria Martha Ramos, a Honduran woman, said some of the officials threw stones to detain people. Ramos said she would see if the main body of migrants regrouped so she could continue her journey north.
The Mexican government recently condemned officials committing acts of violence that were captured on video against the previous group of migrants.
Lopez Obrador said last week that the strategy of containing migrants in southern Mexico was untenable on its own and more investment was needed in the region to keep Central Americans from leaving their homes.
Meanwhile, local migration advocates expressed dismay at the tactics used against the caravan.
Heyman Vazquez, a priest in Huixtla and advocate for asylum seekers, described the early morning swoop on the caravan, which included many children, as an “inhumane” and “cruel” abuse of power that had spread fear and alarm among the travellers.