Guatemala has stationed guards and barbed wire barricades at key border crossing with Honduras in an apparent attempt to stop more migrants marching towards US.
Police officers and what appear to be soldiers in combat fatigues were pictured blocking the road and checking trucks at the Aguas Calientes crossing point, which was used by the first two caravans to enter the country.
It comes after President Trump vowed to cut aid money to any nation failing to stop the migrants, which for Guatemala amounted to more than $230million in 2017.
The Aguas Calientes route has been used by two caravans of migrants to get into Guatemala – the first one of which has now reached Mexico, and the second of which is still in Guatemala, around 200 miles behind the first.
But according to Mexican newspaper El Universal there could be another 3,000 people heading for the Guatemalan border, which authorities are hoping to block.
El Universal, quoting the Mexican National Migration Institute, reports that around 7,000 migrants have already crossed into their country from Guatemala, despite attempts to block them at the border.
Another 3,000 are stuck at the border crossing in Ciudad Hidalgo, the newspaper reports, while applying for paperwork to enter Mexico legally.
Another 3,000-4,000 people are gathered around the border between Honduras and Guatemala, including some who have already crossed and are now heading for Mexico.
The first caravan had been advancing across Mexico at the rate of 20 miles per day, reaching the town of Huixtla on Monday night, but have paused for a day to honor a man who died falling from a truck.
Mexican authorities say they are providing limited food, water and medical supplies to those in the caravan, including children running high temperatures from the long march.
Meanwhile a second caravan, believed to number around 1,500, spent Monday night in the town of Chiquimula, Guatemala, and were pictured hitching rides on trucks on Tuesday as they continued across the country.
Once in Mexico, both groups face an arduous march of at least 1,000 miles to the nearest border crossing point with the US in McAllen, Texas.
It is expected that many will drop out along the route and either return home or apply to reside in Mexico, as happened with another group who made the journey earlier this year.
Mexico says immigration authorities have now received 1,699 refugee applications. Those people are no longer with the caravan and are being sheltered in the city of Tapachula.
Another 495 Hondurans have voluntarily decided to return to their home country with assistance from Mexico.
The majority of those fleeing Honduras say they are seeking a better life in America, blaming a lack of jobs, rampant corruption and soaring crime for leaving.
In Honduras, around 80 per cent of workers earn below the minimum wage of a few hundreds dollars per month, with government welfare programs doing little to help since most of the money is siphoned off by corrupt officials.
Further compounding this misery is the fact that more than 90 per cent of crimes go unsolved, including thousands of murders each year.
In 2012, Honduras had the highest murder rate in the world, and while the government claims there have been significant reductions since then, these figures have not been independently verified.