'Lives in danger'

The policy, launched in January at the San Ysidro port of entry and later expanded to El Paso, Texas, requires asylum seekers to stay in Mexico until their scheduled court date in the US. They had previously been allowed to remain in the US while awaiting their court hearings.

The US has defended the policy as necessary to deter "baseless" asylum claims that "exploit" the country's immigration laws.

But critics argue that forcing migrants to wait in Mexico puts their lives in danger because of violence, crowded encampments and vulnerability to local gangs. They said the policy also violates their legal right to seek asylum in the US.

On April 8, a federal judge in California blocked the policy after finding the administration had not done enough to ensure asylum seekers' safety.

Only a few days after the practice was halted, the 9th Circuit Court of Appeals granted the US government's emergency motion to stay the lower court's ruling. The practice resumed on April 16.

Trump has repeatedly threatened to close the border with Mexico and impose a 25 percent tariff on all cars made there if Mexico stops apprehending migrants trying to cross into the US.

The Mexican government has discouraged migrants from continuing their journey north and urged them to stay in the country by granting them a large number of humanitarian visas, according to media reports.

Doris Meissner and Sarah Pierce, policy analysts at the Migration Policy Institute, said in an article published on the organization's website that the Trump administration's measures, including the zero-tolerance policy that led to family separations, have seemingly encouraged prospective migrants to travel to the US before such policies are hardened further.

In the fiscal year that began on Oct 1, the number of "unaccompanied children" and "family units" apprehended along the southwest border has reached 225,482, representing 62 percent of all apprehensions, according to the figures released by US Customs and Border Protection on April 9.

Despite the rise in the number of asylum-seeking families, the total number of border apprehensions last year was lower than for most of the past six decades, according to CBP data.

The CBP southwest border sector reported 396,579 apprehensions in the 2018 fiscal year, compared with more than 1 million in the 1980s, '90s and early 2000s.

Many factors are behind the recent increase in arrivals, such as endemic violence, limited economic opportunities and poor governance in the Northern Triangle area, as well as available jobs and long-standing social and family ties in the US, the article by Meissner and Pierce said.

Many people from that area fleeing to the US border are banding together and traveling in "caravans" for safety. While only a small percentage have arrived in such caravans, their emergence may have inspired more people to go to the US.

In front of a liquor store near the Otay Mesa port of entry in Tijuana, Gutierrez, the car cleaner, showed a local newspaper article that reported 1,100 migrants from Central America were arriving in Mexico.

He saw migrants climb over the border fence near the beach and turn themselves in to US agents. "If home is safe, who would want to flee?" Gutierrez asked.