The first members of a large group of migrants travelling through Mexico towards the United States have arrived in the capital, Mexico City.
About 450 people, mostly men and boys, were given temporary shelter at a sports stadium.
They are part of a now 5,000-strong group, known as the migrant caravan, which left Honduras on 12 October.
US President Donald Trump says troops will be deployed to stop them crossing the US-Mexican border.
Critics have accused Mr Trump of using people's fears of illegal immigration to fire up his supporters ahead of Tuesday's mid-term elections.
It has taken this group of migrants more than three weeks to get from the crime-ridden Honduran city of San Pedro Sula to Mexico City.
They say they left Honduras for fear of violence and to escape poverty and unemployment.
Many said that reaching Mexico City felt like a major milestone after three weeks of crossing Guatemala and southern Mexico, mainly on foot.
Mexico City, the first major metropolis the migrants have reached since leaving Honduras, is expected to be the place where the caravan may divide and some may decide to stay.
Mexican officials said legal advisers would be on hand to talk those arriving through their options.
Honduran migrant Jackson García is one of those considering asking for asylum in Mexico. "If I can find a job so as to support my family [I will stay in Mexico]. My family is very poor and I need to help them," he said.
But many others, such as Carlos Flores, remain determined to continue to the US: "The little that you get in US dollars goes a long way in Honduras. But what you earn here [in Mexico] not so much, you have to pay for food, room, things are expensive here."
Mauricio Mancilla, who has travelled from northern Honduras with his six-year-old son, says for him his destination has always been clear: "Our heads are set at getting to the United States, to fulfil the American dream. We have faith in God that we will do this, whatever the circumstances."
More on the way
President Trump has put pressure on the Mexican authorities to stop the migrant caravan, which he has called "an invasion". He has also said that he will use the military to completely close the US-Mexico border if necessary, to stop the migrants crossing into the US.
After briefly stopping them at Mexico's southern border with Guatemala, the Mexican authorities have not stood in the way of the migrants.
The governor of Veracruz, Miguel Ángel Yunes, on Friday offered to lay on free buses to take the migrants crossing his state to Mexico City, but he later withdrew the offer.
In the capital, city officials prepared food and shelter as well as medical services to those arriving at the Jesús Martínez "Palillo" stadium.
"There are pregnant women, many children, vulnerable people and we have to guarantee the space and the services they require," said city leader José Ramón Amieva Gálvez.
Many of those arriving were so exhausted they only grabbed a blanket before falling asleep. "From what I brought from Honduras I have nothing. Even yesterday I walked barefoot," Kenia Alvarado, 21, told El Universal newspaper.
Residents of Mexico City have donated clothes and shoes for the travellers, local media reported.
Apart from the approximately 5,000-strong group approaching Mexico City, there are two more groups of migrants heading north. One has only just crossed the Suchiate river, which marks the border between Mexico and Guatemala, and the other is moving north from Mexico's southern Chiapas state.
It is expected all three groups will meet up in Mexico City and that those who remain determined to make it to the US will set off together.