Thousands awakened as the sun rose over a makeshift encampment in a rain-soaked square in the far southern Mexican town of Huixtla, a chorus of coughs rattling from the shapeless forms wrapped in blankets and bits of plastic sheeting.
Sunburned from the daytime heat and chilled by the overnight cold, many appeared to be developing respiratory problems.
Edwin Enrique Jimenez Flores, 48, of Tela, Honduras, had one of those persistent coughs, but still vowed to reach the U.S. to seek work.
"My feet are good," he said.
A mobile medical clinic truck pulled into the square in the morning to offer the migrants treatment. Municipal worker Daniel Lopez said the town was offering food and water as well as basic painkillers and rehydration liquids, and some children were running high temperatures.
Overnight, candles arranged in the shape of a cross were lit in a simple memorial to the dead Honduran man , who fell from the back of an overcrowded truck Monday as it traveled on a highway.
"Today we won't move. Today is a day of mourning," said Irineo Mujica, whose Pueblo Sin Fronteras group has been aiding migrants. He added that they would leave before dawn Wednesday headed for Mapastepec, about 38 miles (60 kilometers) up the coast.
Such caravans have taken place regularly over the years, generally without great fanfare, but U.S. President Donald Trump has seized on the phenomenon this year and made it a rallying call for his Republican base ahead of Nov. 6 midterm elections.
Trump has blamed Democrats for what he said were weak immigration laws and claimed - with no evidence - that MS-13 gang members and unknown "Middle Easterners" were hiding among the migrants.
The caravan, estimated to include more than 7,000 people, has advanced about 45 miles (75 kilometers) since crossing the border from Guatemala and still faces more than 1,000 miles to the closest U.S. border crossing at McAllen, Texas - and more than twice that to reach the distant Tijuana-San Diego crossing. Many in the caravan have low odds of qualifying for asylum even if they do make it, as the United States does not consider things like fleeing from poverty or gang violence as a qualifying factor.
A smaller caravan earlier this year headed for the California crossing, dissipating as it advanced, and only about 200 of the 1,200 in that group reached the border.
Nearly 1,700 from the current caravan have already dropped out and applied for asylum in Mexico, according to Mexican authorities, and another 500 have decided to voluntarily return home to Honduras. And the numbers could thin out far more as people decide to take their chances in Mexico or strike out on their own.
In Huixtla, the morning routine began with lines of people brushing their teeth and spitting toothpaste into the gutters. Donations of food and other supplies were brought in, and as garbage piled up in the square, the migrants tried to organize it into piles so it could be carted away.
Wilfredo Anaya of San Pedro Sula, Honduras, passed among them collecting coins in a foam cup to buy plastic garbage bags to leave the plaza clean.
"We all pitch in among ourselves," Anaya said, "because this thing will go on for a while."
Portable toilets were set up in one corner of the overflowing plaza. A few hundred people were also camped out on a basketball court outside of town, where there were no bathrooms and little donated food.
With no sophisticated medications or doctors available, scant lavatories, and largely private donations of aid, activist Mujica accused Mexico's government of intentionally trying to wear down the migrants.
"It isn't acting responsibly in light of the situation," said Mujica. "This is a tactic to affect people's wellbeing even more."
Slender and sunbaked, Selvin Antonio Guzman of Santa Barbara, Honduras, said, like many others, that he left home because gangs extorting protection fees were making life impossible.
Guzman would have joined his mother and sister in the United States years ago but never had the thousands of dollars needed to pay a smuggler. So he jumped at the chance for the relative safety in numbers and far cheaper alternative that the caravan offered.
Despite the rough conditions, he said that "every day we feel stronger. You see the women and children walking, and feel that there's no turning back. ... I know I am going to make it. We are giving each other strength."
Adrian Edwards, a spokesman for the U.N. High Commissioner for Refugees, said in Geneva that "in any situation like this it is essential that people have the chance to request asylum and have their international protection needs properly assessed, before any decision on return (or) deportation is made."
Trump has criticized Guatemala, Honduras and El Salvador for not stopping people from leaving their countries and said in a tweet on Monday that the U.S. would "now begin cutting off, or substantially reducing, the massive foreign aid routinely given to them." He has also threatened to use the military to close down the United States' southern border.
Still, administration officials have not indicated any action in response to what Trump tweeted was a "National Emergency."
Mujica, the migrant rights activist, said Trump is trying to stir up his Republican base by making political hay out of the caravan and border security ahead of the November vote.
"You could say the one who benefits most is him," he said. And, "if the caravan stops, who wins? Him."
In interviews along the journey, migrants have said they are fleeing violence, poverty and corruption.
Jimenez Flores, a truck driver, said he couldn't return to Honduras because a gang attacked his brother and threatened him with death after he called police recently.
"I spent four months hidden. I couldn't even go into the street," Flores said. "I can't go back."
Associated Press writer Peter Orsi in Mexico City contributed to this report.
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