
President Trump has doubled down on his claim that there are dangerous people 'from the Middle East' among the 7,200-strong migrant caravan making its way towards the US and says he will spare no expense or resource in stopping them from entering the country.

Speaking on board Air Force One on Monday night, the president told USA Today that he was prepared to send 'as many troops as necessary' to stop the thousands of Hondurans and Guatemalans making their way to the border.

Repeating his earlier remark that the Democrats were to blame for it, he said: 'I think this could be a blessing in disguise because it shows how bad our laws are. The Democrats are responsible for that.'

He was on his way to a campaign rally in support of Texas Sen. Ted Cruz where he described the caravan as an 'assault on the country' that the Democrats were to blame for.

As he spoke, a second caravan of thousands of additional migrants made their way through Guatemala.

Now, the original caravan, which is in southern Mexico, is a mile long. It remains unclear exactly how many are in the second batch but they are making fast progress through Guatemala.

In Mexico, there were new fears over the migrants' safety after a man died falling from the back of a loaded-up truck carrying hordes of people.

Police in Tapachula, where the accident happened, have started ordering overcrowded trucks off the road and demanding that the migrants continue on foot.

Among the migrants are deportees who say they are determined to resume their old American lives despite being thrown out either by Trump's administration or those before him.

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President Trump appeared at a rally for Texas Sen. Ted Cruz on Monday night where he repeated claims that the Democrats were to blame for the caravan and said it was an 'assault' on the country

Job Reyes, a 36-year-old who was previously deported, told The Washington Post: 'It’s time for me to go back to the United States. It’s a country where I can live my life, unlike Guatemala.

'When I heard about the caravan, I knew it was my chance.'

The UN has warned that many of those making the journey are at risk of being kidnapped or trafficked as they gradually walk through Mexico.

Adrian Edwards, a spokesman for the U.N. High Commissioner for Refugees, said Tuesday in Geneva the agency is concerned about 'the developing humanitarian situation and the known kidnapping and security risks in areas the caravan may venture into.'

'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,' he added.

President Trump is however confident that the migrants pose the biggest threat.

This was the border bridge between Guatemala and Mexico on Tuesday morning. It was empty for the first time in days after thousands crossed over during the weekend. The second caravan is on its way

A migrant rolls up his sleeping mat after spending the night in Huixtla, Mexico, on Tuesday morning. They walked eight hours to get there before setting up camp for the night

Migrants slept beneath plastic sheets on Monday night in Huixtla, Mexico. It is their latest stop after arriving in Chiapas, Mexico's southernmost state

A Central American migrant waits for others to wake up in Huixtla, Mexico, on Tuesday morning before the sunrise

A migrant prays in the street after waking up in Huixtla, Mexico, on Tuesday morning before another day of trekking

A young man sleeps in the street as his neighbor packs away the sheet he slept on after spending another night in the streets. The main caravan set off from San Salvador in Honduras on October 13

Men wash their faces and brush their teeth in the streets of Huixtla, Mexico, on Tuesday morning before setting off for the day. Mexico had promised to help the US by stopping the migrants from entering their country but they have done little to stop the crowds' plans. On Friday, officials put some of them on buses to take them away from the border crossing

At daybreak in Huixtla, Mexico, on Tuesday, there were still candles burning from the night before. Thousands of people are sleeping in the streets

The first caravan set off from San Salvador last week and crossed through Honduras and Guatemala with relative ease before arriving at Mexico's border with Guatemala on Friday. After briefly clashing with police, they were let through and are now marching north towards the US. The second caravan is now in Chiqimula, Guatemala, and is being bused to the border to catch up with the others

In a flurry of comments outside the White House on Monday afternoon, he said: 'I have reports that they've got a lot of everybody in that group. It's a horrible thing.'

He insisted during one exchange that a mid-morning tweet about '[c]riminals and unknown Middle Easterners' would be proven true – that they're really there – if reporters would only look in the right places.

'You know what you should do?' Trump asked. 'Go into the middle of the caravan. Take your cameras and search, okay?'

'Go into the middle and search,' the president said. 'You're going to find MS-13. You're going to find Middle Eastern[ers].

'You're going to find everything. And guess what? We're not allowing them in our country. We want safety. We want safety.'

Democrats and Republicans have fought for days about how to describe the latest sea of humanity known as a migration 'caravan.'

Caravan 2.0: In addition to the 7,200 migrants who are in the first group, a second caravan has formed in Guatemala and is preparing to cross the border into Mexico. They are pictured on Monday night as they arrive in Chiquimula, 280 miles from Mexico's border

It is unclear exactly how many additional migrants are in the second caravan. They are shown on Monday night, making their way past Guatemalan police officers

The second group are in west Guatemala in Chiquimula. On Monday, they were put on buses which will drive them the 280 miles they need to cross to get to the Mexican border. Then, they will join lines of hundred of remaining migrants from the first caravan to get over the Mexican border and continue up towards the US

There were still hundreds of people trickling over Guatemala's border with Mexico on Monday. Some are shown above being lined up on Monday before being let over the border gate. Mexico suddenly decided to start allowing them in on Friday after initially promising not to. The move infuriated President Trump who has since threatened to cut off aid to Central America in retaliation

Caravan: As many as 7,000 people are now traveling in the caravan which was seen from the air in Tapachula, in southern Mexico - still 1,600 miles from the U.S. border

Any way to get north: These Hondurans have a ride for part of the journey through Guatemala and Mexico and hope to cross into the U.S., but President Trump says he's alerted America's military and border control agencies

On the road: The migrant caravan was in Metapa, in the southern Mexican state of Chiapas, Monday, at the same time as Trump was tweeting that it was a 'national emergency' in the U.S.

On the move: Honduran migrants used a truck to get further into Mexico in Tapachula on Monday

Pressure: The city of Tapachula has seen Miguel Hidalgo Park become ground zero for members of the migrant caravan sleeping rough

Having crossed the border between Mexico and Guatemala, the migrants reached the town of Huixtla on Monday night and appear to be traveling around 20 miles per day

After the town square in Tapachula was turned into a resting place for the migrants, on Monday night it was the turn of Huixtla to play host to the caravan

At their current pace it will take the migrants around 80 days to cross Mexico on foot, meaning they will arrive at the southern US border shortly after New Year

Men, women and children taking part in the long march from Honduras to the US rest in the Mexican town of Huixtla

Migrants sleep under temporary shelters in the town of Huixtla, in the southern Mexican state of Chiapas, on Monday night

The caravan started out in Honduras earlier this month and has already marched more than 300 miles across Guatemala to reach Mexico (pictured), but now faces a 1,600 mile slog to the US border

A Honduran woman attempting to make it from her home country to the US sits outside a temporary shelter in town of Huixtla

Not everyone from the original caravan has made it into Mexico. Here, several hundred people wait on a bridge between Guatemala and Mexico to be admitted legally

Migrants hoping to enter Mexico legally from Guatemala sleep in camps near the border crossing point

To the political left, they're asylum seekers fleeing poverty and civil wars driven by narco-trafficking. On the right they're seen as opportunists, urged by Trump's political adversaries to be as visible as possible in the days leading up to a congressional election and nudge Democrats to the polls.

Trump has largely blamed the governments of Guatemala, Honduras and El Salvador, warning that he'll turn off the foreign-aid spigot as punishment for threatening U.S. border security.

'Every year we give them foreign aid, and they did nothing for us. ... Hundreds of millions of dollars. They, like a lot of others, do nothing for our country,' he fumed Monday.

Observers on the ground have said the migrant exodus is largely controlled by drug cartels and human traffickers, not government agencies.

The president claimed that the caravan had grown to become 'a lot bigger than 5,000 people,' citing the most common figure in news reports, 'and we've got to stop them at the border.'

He complained earlier on Twitter that Mexico has been unable to stop the migrants who have captured humanitarian interest while they've piqued his outrage.

'Sadly, it looks like Mexico’s Police and Military are unable to stop the Caravan heading to the Southern Border of the United States. Criminals and unknown Middle Easterners are mixed in. I have alerted Border Patrol and Military that this is a National Emerg[enc]y. Must change laws!' he tweeted.

The president also returned to his political messaging just 15 days before the midterm congressional election, saying voters who fear the impact of a mass influx of illegal immigrants should elect more Republicans.

'Every time you see a Caravan, or people illegally coming, or attempting to come, into our Country illegally, think of and blame the Democrats for not giving us the votes to change our pathetic Immigration Laws! Remember the Midterms! So unfair to those who come in legally,' he said.

The Department of Homeland Security is warning that Mexico's cartels will try to 'prey on the vulnerabilities' of migrants in the caravan, now 7,000 strong.

Despite President Trump's hardline rhetoric, a second caravan has now formed and is roughly 200 miles behind the first. Here, members of the new caravan are pictured in Chiquimula, Guatemala

More Honduran migrants taking part in a second caravan heading for the US are pictured in Guatemala on Monday night

It is not clear how many people are participating in the second migrant caravan, though the first is said to number up to 7,000

Young men traveling as part of a second migrant caravan cross Guatemala as they attempt to reach the US, 1,000 miles away

Guatemalan police confront Honduran migrants in the town of Chiquimula as they pass through on their way to America

DHS Secretary Kirstjen Nielsen warned that criminals and people smugglers will be hunted down and 'prosecuted to the fullest extent of the law.'

Nielsen spoke as thousands marched on through Mexico toward the U.S. on Sunday after evading fences and guards along the border with Guatemala.

Up to 7,000 people are now traveling in the caravan, according to the Los Angeles Times; the Associated Press reported 5,000 and AFP counted as few as 3,000.

Several thousand are thought to have returned home, some on buses provided by the Guatemalan government, after being blocked at the Mexican border.

But a new group of 1,000 Hondurans have begun the journey, vowing to following in the footsteps of the first.

Mexican officials say 640 people stopped at their border before applying for legal refuge, including 164 women, more than 104 children and teenagers, and many older and disabled people.

Of those who managed to cross the border most ended up in a town called Tapachula, around 20 miles from the border at Ciudad Hidalgo, where they rested on Sunday night before continuing their march.

They now face a daunting slog of 1,600 miles across Mexico before reaching the U.S. border, where President Trump has vowed to turn them away.

Hefired off a tweet on Sunday afternoon, saying: 'Full efforts are being made to stop the onslaught of illegal aliens from crossing our Southern Border.

'People have to apply for asylum in Mexico first, and if they fail to do that, the U.S. will turn them away. The courts are asking the U.S. to do things that are not doable!'

Mexican border guards initially drew praise from Trump for their hard line approach after stopping thousands of people from crossing into the country using riot shields and tear gas.

But many later crossed the river on makeshift rafts, or were helped across by sympathetic Mexicans who loaded them into pickups, vans and cargo trucks before driving across.

On their way: Members of the caravan get on the back of truck as they try to make their way north from Tapachula

Assistance: These members of the caravan had crowded into the back of a truck to get to the city of Tapachula, after crossing the border from Guatemala into Mexico

The president said Monday that he has alerted the U.S. military about a national emergency

He reminded the governments of Honduras, Guatemala and El Salvador on Monday that the aid money they get from Washington could dry up

Cool down: Central American migrants use a fire hydrant in the main plaza of Tapachala, the city just across the Mexican border where as many as 7,000 are now gathered

Crossing to Mexico: Migrants are using rafts to cross the Suchiate River, the barrier between Mexico and Guatemala, to avoid military and borer patrols

Impact: In Tapachula public authorities are facing huge numbers of people sleeping outside, especially in Miguel Hidalgo Park

Emergency measure: Red Cross tents have been put in place in the arena used for the annual International Mesoamerican Fair in Tapachula

Sleeping rough: One of the Honduran migrants who has made it to the border at Tecan Uman, Guatemala, sleeps as he waits for his claim to be processed

On the road: Local trucks have been moving people who started in Honduras and are now in Mexico on their way to Tapachula

Ready for arrivals: These tents have been erected at the International Mesoamerican Fair's former venue in Tapachula in anticipation of even more people crossing the border

The Department of Homeland Security has vowed to crack down on Mexican cartels trying to help a caravan of thousands of desperate migrants cross from Mexico into the US (pictured, part of the caravan in Mexico)

Around 3,000 people have crossed from Guatemala into Mexico since arriving on Friday, down from around 5,000 after many gave up and returned home (pictured, migrants in Mexico)

The caravan continued to march across Mexico on Monday despite threats from President Trump to stop anyone who had not applied for legal asylum at the US border

Dozens of migrants rest in the main square in Tapachula, Mexico, on Sunday having walked from Ciudad Hidalgo, around 20 miles away on the border with Guatemala

Migrants wave a Honduran flag having crossed the border between Guatemala and Mexico, where they have vowed to continue on to the United States

A young Honduran girl eats in the main square in Tapachula, Mexico, after successfully crossing the border from Guatemala

Speaking on Sunday about the group who had crossed into Mexico, Nielsen said: 'While we closely monitor the caravan crisis, we must remain mindful of the transnational criminal organizations and other criminals that prey on the vulnerabilities of those undertaking the irregular migration journey.

'We shall work with our partners in the region to investigate and prosecute to the fullest extent of the law all who seek to encourage and profit from irregular migration.

'We fully support the efforts of Guatemala, Honduras and Mexico, as they seek to address this critical situation and ensure a safer and more secure region.'

Aaron Juarez, 21, a migrant walking through Mexico with his wife and baby while limping from an injury, vowed that 'no one is going to stop us' from getting into the U.S. '[Not] after all we've gone through.'

Honduran farmer Edwin Geovanni Enamorado said he was forced to leave his country because of intimidation by racketeering gangs. 'We are tired, but very happy, we are united and strong,' he said.

Britany Hernandez added: 'We have sunburn. We have blisters. But we got here. Our strength is greater than Trump's threats.'

Mexico's President-elect Andres Manuel Lopez Obrador called for fair treatment of the migrants.

President Trump has taken an unusually hard line against Central American countries ina bid to force them to retrieve their own people instead of allowing them to march north through Mexico

A pickup truck owned by a Mexican driver helps migrants to cross the border from Guatemala, followed closely by another driver doing the same thing (left)

Having already walked to Mexico from Honduras, almost 350 miles away, the migrants now face a trek of 1,600 miles across Mexico in order to reach the U.S. border

Paramedics check the blood pressure of a migrant in Tapachula, after he made his way across the border

Mexican medics treat a Honduran child in Tapachula after their family made the crossing from Guatemala at the weekend

Migrants on the Guatemalan side of the border wait to cross into Mexico after being stopped by guards

Guatemalan officials fumigate the main bridge between their country and Mexico which has been crowded by thousands of migrants in recent days

'We don't want them to face what (Mexicans) face when they need to look for work in the United States,' he said on Twitter.

The caravan left San Pedro Sula in northern Honduras more than a week ago, following a call on social networks relayed by a former Honduran deputy.

The politician, Bartolo Fuentes - a member of leftist former president Manuel Zelaya's Freedom and Refoundation Party - told AFP he only reproduced a poster on his Facebook page.

The poster invited people on a 'Migrant march' with a slogan: 'We're not leaving because we want to, but because we are being expelled by violence and poverty.'

Morales and his Honduran counterpart Juan Orlando Hernandez said after meeting that the march was 'violating the borders and the good faith of the states.'

The Honduran president acknowledged that social problems were a contributory factor.

'Without a doubt, we have a lot to do so that our people can have opportunities in their communities,' he said.

Migrants denied their motives were political.

'We decided to join those who were going,' said Edgar Aguilar. This is not political. This comes from hunger, from the drought, it's for prosperity, for a better life. This is not political!'

The migrants are generally fleeing poverty and insecurity in Honduras, where powerful street gangs rule their turf with brutal violence.

With a homicide rate of 43 per 100,000 citizens, Honduras is one of the most violent countries in the world, according to a Honduran university study.