
Sickness, fear and police harassment have slowly whittled the size of the migrant caravan, but thousands remained on the northward march even as Defense Secretary Jim Mattis was expected to sign an order sending 800 or more troops to the southern border.

The caravan, still numbering some 4,000 to 5,000, set off from from Mapastepec, Mexico at dawn on Thursday with more than 1,000 miles still to go and the rigors of the trek toward the U.S. taking their toll.

In the 95 miles since the caravan burst through the border with Guatemala over the weekend, about 1,200 have left the caravan. An estimated 500 people have voluntarily accepted bus trips back to their home countries, and 1,700 have dropped out to apply for asylum in Mexico, officials in that country say.

'We didn't know what lay ahead,' lamented Pedro Arturo Torres, homesick for Honduras. 'We want to return to our country, where you can get by — even if just with beans, but you can survive, there with our families, at peace.'

Honduran migrants heading in a caravan to the US, travel on foot or atop vehicles in Mapastepec on their way to Pijijiapan on Thursday. Thousands of Central American migrants have dropped out of the caravan since crossing into Mexico

The sprawling caravan of migrants hoping to make their way to the United States set off again on Thursday, forming a column more than a mile long as the group trekked out of the town of Mapastepec in southern Mexico before dawn

A Honduran migrant carries his national flag as he walks north as part of a thousands strong caravan trying to reach the U.S., still over 1000 miles away, near Mapastepec, Mexico on Thursday

Meanwhile, other migrants are seen boarding a bus on Wednesday night to voluntarily return them to Honduras

A map shows the migrant caravan's progress and a regional overview of other migrant activity as of Thursday morning

As the caravan ground north from Mexico's southern border, Mexican federal police have seen to it that their journey is as unpleasant as possible.

In at least one case, reporters have witnessed Mexican police pulling over a vehicle carrying hitchhikers from the caravan and ordering everyone who wasn't a Mexican citizen to get off of the truck.

Forcing the migrants to walk under the scorching midday heat may eventually take a toll on their health and compel more of them to take free buses back to Honduras.

A taxi driver in the southern Mexico town of Mapastepec also recounted Thursday having seen immigration agents force migrant passengers out of cabs at a checkpoint. Later, hundreds of migrants were given free passage at the same checkpoint as Mexican officials watched.

An official from Mexico's Human Rights Commission said migrants can go through if they are in vans or trucks that offered them rides for free. But if they paid fares, they must get out because of insurance regulations. Migrants may also walk through the checkpoint. The human rights official, who was in uniform, said he was not authorized to speak about the matter and did not give his name.

Cesar Antonio Perez Rodriguez, a migrant from El Salvador, said Mexican immigration agents had forced him, his pregnant wife Delmy Roxana Martinez and their 3-year-old son out of a van on Wednesday. They were brought to a room inside an immigration office that eventually filled with more than 30 migrants.

Hours passed with no explanation for the detentions. Several in the group became agitated and pushed their way free through a door, he said. In the commotion Perez said he grabbed his bag but left his wife and child behind. As he ran he looked back to see his wife blocked by agents wielding batons, holding their son and crying.

A Mexican police car is seen passing a truck carrying migrants on Wednesday. In at least one case, police have ordered all of the migrant hitchhikers off a vehicle and forced the migrants to walk in the scorching midday sun

Central American migrants hitch ride, as a thousands strong caravan heads north hoping to reach the U.S. border, near Mapastepec, Mexico on Thursday. Sickness, fear, and police harassment are whittling down the migrant caravan

Migrants, part of a caravan of thousands from Central America en route to the US, make their way to Pijijiapan on Thursday

Perez made his way Thursday to an internet cafe in Mapastepec, where he desperately tried to contact his wife's relatives via Facebook to find out if they had heard from her. He had no money and his wife had their only cell phone, a Mexican number he didn't know.

'I don't want to lose my son,' Perez said, choking back tears.

In addition, the Mexican federal government has flatly refused to provide any aide to the migrants: not a single meal, a bathroom or a bottle of water.

It has reserved those only for migrants who turn themselves in at immigration offices to apply for visas or be deported.

All the food, old clothes, water and medicine given to the migrants have come from private citizens, church groups or sympathetic local officials.

Carlos Roberto Hernandez, of Yoro province in Honduras, dropped out after developing a rumbling cough during the scorching daytime heat and evening rains.

'We got hit by rain, and ever since then I've had a cold,' Hernandez said. Asked Wednesday if he would make another attempt to reach the U.S., he said emphatically: 'No. I'm going to make my life in Honduras.'

Mexican Marines patrol the Suchiate river, the natural border between Mexico and Guatemala, to prevent migrants from Central America to cross the river using rafts, in Ciudad Hidalgo, Mexico on Thursday

Central American migrants traveling with a caravan to the U.S. make their way to Pijijiapan, Mexico on Thursday

Honduran migrants heading in a caravan to the US, travel standing on the back of a truck in Mapastepec on their way to Pijijiapan Chiapas state, Mexico, on Thursday. Mexican police have been seen ordering drivers not to pick up hitchhikers

Central American migrants traveling with a caravan to the U.S. climb onto to a trailer bed, hitching a ride to Pijijiapan, Mexico

On Thursday morning, the column stretched for more than a mile as the migrants left the Mapastepec town square where many spent the night.

The municipality of some 45,000 people, along with churches and volunteers, offered some medicine and donated water, clothing baby formula and baby bottles.

As they reached the highway, families with young children packed sidewalks asking for donations and rides to the next stop, Pijijiapan, about 25 miles further ahead.

Melkin Claros, 34, was traveling with his seven-year old son and a teenage nephew and remained steadfast in his goal.

'Everyone's objective is to arrive (in the United States),' he said, adding that he planned to request asylum because gangs made it impossible to live in Honduras. 'It's true you risk your life a lot here, but we risk more in our country.'

Honduran migrants walking north wave the flags of Honduras and Mexico to passing trucks carrying migrants, as a thousands strong caravan heads north trying to reach the U.S., still over 1000 miles away, near Mapastepec, Mexico on Thursday

In Mapastepec, where the main group stayed Wednesday night, it appeared the size of the caravan had diminished slightly.

The United Nations estimated earlier in the week that about 7,000 people were in the group. The Mexican government gave its own figure Wednesday of 'approximately 3,630.'

Parents say they keep going for their children's futures, and fears of what could happen to them back home in gang-dominated Honduras, which was the main motivation for deciding to leave in the first place.

'They can't be alone... There's always danger,' said Ludin Giron, a Honduran street vendor making the difficult journey with her three young children. 'When (gang members) see a pretty girl, they want her for themselves. If they see a boy, they want to get him into drugs.'

Refusing either demand can be deadly. Honduras has a homicide rate of about 43 per 100,000 inhabitants, one of the highest in the world for any country not in open war.

On Wednesday, Giron crammed with her children, three-year-olds Justin and Nicole and five-year-old Astrid, into the seat of a motorcycle taxi meant for only two passengers. Also perched on the perilously overcrowded motorbike were Reyna Esperanza Espinosa and her 11-year-old daughter, Elsa Araceli.

Honduran migrants taking part in a US-bound caravan travel from Mapastepec to Pijijiapan Chiapas state, Mexico, Thursday

Honduran migrants heading in a caravan to the US, walk alongside the route in Mapastepec on their way to Pijijiapan

Aerial view of Honduran migrants taking part in a caravan heading to the US, walking and travelling aboard a truck near Mapastepec, southern Mexico on Thursday

Espinosa, a tortilla maker from Cortes, Honduras, said there was no work back home. 'That's why we decided to come here, to give a better future for our children,' she said.

Such caravans have taken place regularly, if on a smaller scale, over the years, but Trump has seized on the phenomenon this year and made it a rallying call for his Republican base ahead of the November 6 midterm elections.

On Thursday morning, President Donald Trump ordered hundreds of troops to fortify the southern border of the U.S. ahead of the caravan's arrival.

'I am bringing out the military for this National Emergency. They will be stopped!' Trump tweeted early on Thursday.

Defense Secretary Mattis was expected to sign deployment orders that could send 800 or more troops to the border with Mexico to help border patrol authorities, a U.S. official said.

The U.S. official was not authorized to speak publicly because not all details of the military arrangement had been worked out, and so spoke on condition of anonymity.

Honduran migrants heading in a caravan to the US, climb up a truck in Mapastepec on their way to Pijijiapan on Thursday

Thousands of Central American migrants crossing Mexico toward the United States in a caravan have resumed their long trek, walking about 12 hours to their next destination

Honduran migrants heading in a caravan to the US, travel on foot or atop vehicles in Mapastepec on their way to Pijijiapan

The additional troops are to provide what one official described as logistical support to the Border Patrol.

THIRD CARAVAN PLANNED IN EL SALVADOR A group of around 250 people is planning to set off from El Salvador in what will become a third migrant caravan on October 31. According to NBC, White House officials are monitoring the group which is discussing its plans over WhatsApp. Though the group is significantly smaller than the others already on their way, US officials are particularly concerned that it may include members of MS-13, an El Salvadorian gang notorious for recruiting youngsters and applying unthinkable violence to its rule. Advertisement

This would include a variety of things such as vehicles, tents and equipment, and perhaps medical support.

It was not immediately clear how many, if any, of the extra troops would be armed. Because they would not be performing law enforcement duties they would not be in violation of the Posse Comitatus Act, which prohibits the federal government from using the armed forces in a domestic police role.

There already are about 2,000 National Guard troops assisting at the border under a previous Pentagon arrangement.

It is unknown where along the border the new troops would be sent, or where the caravan will attempt to cross.

Although southern Texas is the closest crossing from the caravan's current location, trains running from Mexico City to Tijuana make southern California an attractive crossing point for many of the migrants.

Trump has blamed Democrats for what he says are weak immigration laws, and he claimed that MS-13 gang members and unknown 'Middle Easterners' were hiding among the migrants.

He later acknowledged there was 'no proof' of the claim Middle Easterners were in the crowd. But he tweeted Wednesday that the U.S. 'will never accept people coming into our Country illegally!'

Honduran migrants wait to board a bus at the service of the Mexican National Migration Institute, to voluntarily return to their home country, in Huixtla, Mexico on Wednesday

Honduran migrants can be seen here waiting to board a bus back to Honduras on Wednesday, which was provided at the service of the Mexican National Migration Institute

Journalists traveling with the caravan have met throngs of Hondurans, as well as Guatemalans, Salvadorans and Nicaraguans, but no one from the Mideast.

Another, smaller caravan earlier this year dwindled greatly as it passed through Mexico, with only about 200 making it to the California border.

Those who do make it into the U.S. face a hard time being allowed to stay. U.S. authorities do not consider poverty, which many cite as a reason for migrating, in processing asylum applications.

Carmen Mejia from Copan, Honduras, carried 3-year-old Britany Sofia Alvarado in her arms, and clutched the hand of 7-year-old Miralia Alejandra Alvarado, also sweaty — and feverish.

Mejia said she was worn out. Still, she pledged to go on. 'I've walked a long way. I don't want to return. I want a better future for my children.'