It came amid a surge in the number of undocumented migrants seeking to enter the US.
An analyst told Insider that a perfect storm of factors is driving people north to the border.
Ariel Ruiz, an analyst at the Migration Policy Institute, said that the factors driving migration are "intersecting and compounding," and driving the surge from Central America, South America and the Caribbean.
In Venezuela, Cuba and Nicaragua, increased political repression and inflation related to the COVID-19 pandemic are key factors driving the surge, while in Haiti, he said, a surge in gang violence was the main driver.
The wealth available in the US, the relative poverty of other nearby nations, and limited options for legal migration, mean that high undocumented migration is likely to continue, Ruiz concluded.