June 16 (UPI) -- Mexico said Sunday it detained nearly 800 migrants crammed into four trucks amid heightened pressure from the Trump administration to stem the number of people entering the United States illegally.
Mexico's National Migration Institute said in a statement that it had detained 791 migrants discovered in trucks on Saturday in eastern Mexico.
The drivers of the trucks have been arrested, it said.
Mexico said the detentions come as the country has deployed 1,000 migrant agents to its northern and southern borders in operations to verify the visas of non-Mexicans who are traveling through the country.
The increase in migrant agents is part of a June 7 agreement between the two countries that would see Mexico beef up measures to stop Central American migrants from crossing the U.S.-Mexico border in return for the Trump administration not fulfilling threats to impose a 5 percent tariff increase on all goods imported from Mexico.
The deal came amid an influx in migrants attempting to enter the United States through its southwestern border. In May, U.S. Customs and Border Protection said it apprehended 132,887 people compared to 99,304 a month earlier and 51,008 in October.
Meanwhile, on Friday, Mexico's National Migration Institute president, Tonatiuh Guillen Lopez, submitted his resignation, the department said in a statement on Twitter.
He was replaced by Francisco Garduno Yanez.
The Saturday apprehensions were part of his "first actions," the Sunday statement said.
The issue of migrants entering the United States illegally has long been of concern for Trump, who during the 2016 presidential election campaigned to stem the influx through building a U.S.-Mexico border wall among other similar moves.