Police boarded buses and headed further down the highway, while migrants cheered and vowed to trek all the way to the USA border despite fierce opposition from President Donald Trump.
Coordinators of the caravan read out the president's plan called "You are at home". They then added: "No, we're heading north!"
The standoff comes after one of the caravan's longest days of walking and hanging from passing trucks on a 60-mile journey to the city of Arriaga.
Taking aim at the caravan of Central American migrants, Mr Trump wrote on Twitter on Thursday he was "bringing out the military for this National Emergency".
The group planned to set out early Monday for Niltepec, 43 miles to the northwest in Oaxaca state.
An estimated 1,700 migrants who were part of the caravan requested asylum after crossing the border into Mexico. Nielsen called it a significant accomplishment to keep immigrants out.
In its information, the Hope Border Institute says the group may arrive at the U.S. -Mexico border "sometime between Thanksgiving and Christmas, or possibly sooner" and faith-based and other human rights groups are preparing to help.
"Rows of police impeded the migrants' path, prompting several hours of negotiations between police commanders, immigration officials and caravan representatives", the AZ Central said. Only about 200 in that group made it to the border. The first migrants must reside in the States of Oaxaca or Chiapas.
An initial caravan of migrants - now comprising some 7000 people, mainly Hondurans - departed from San Pedro Sula on October 13 heading for the USA and a large number of them are currently traversing far southern Mexico on foot after making it through Guatemala.
The migrants will be bussed to immigration processing centers for possible repatriation.
The caravan, which began in Honduras almost two weeks ago and picked up other Central Americans along the way, has angered Trump, who has maintained a hard-line on immigration.
However, it now appears such smaller groups will be picked off by immigration authorities, keeping them from swelling the caravan's ranks.
The caravan is now trying to strike out for Tapanatepec, about 29 miles up the road.
"I would like her to remember that I am doing this to give her a better life, to give good schooling, to give her what I never had in my childhood", Gutierrez said.
Mexican television showed a migration officer telling Hondurans behind the metal gate that they needed to follow "legal procedures" to enter the country in a "calm and safe way".
Caldames says: "My blood pressure is bad".
On Sunday, while the band of migrants was resting and reorganizing in Tepanatepec, several hundred in another group more broke through border barriers in the Guatemala town of Tecun Uman just as members of the caravan did more than a week earlier. It was unclear as of Friday if any of the USA forces would be armed. It says it's working with Mexican authorities to provide drinking water and hygiene products.
The mobilization of migrants is believed to have formed sometime in mid-October and comprised of mostly Honduran migrants seeking refuge from violence and poverty at home.
A severely dehydrated woman connected to an IV line sat on a plastic chair in the gazebo.
For more than a week, thousands of migrants from Central America have been making their way doggedly north towards the US.