In Photos: Thousands of Honduran Migrants March Towards U.S.

A U.S.-bound caravan of thousands of mostly Honduran migrants whom President Donald Trump has declared unwelcome, crowded into the Mexican border city of Tapachula on Sunday, setting up impromptu camps in public spaces under a heavy rain.

Members of the caravan, exhausted from the hours-long trek on foot from the Guatemalan border, mostly ignored police offers to board buses heading to a migrant shelter because of suspicions they might be deported instead.

The migrants have defied threats by Trump that he will close the U.S.-Mexico border if the caravan advances, as well as warnings from the Mexican government that they risk deportation if they cannot justify seeking asylum in Mexico.

On Sunday, Trump said on Twitter that "full efforts are being made to stop the onslaught of illegal aliens," arguing that the migrants must apply for asylum in Mexico before attempting to petition U.S. authorities.

In southern Mexico, police in riot gear shadowed the caravan's arrival along a southern highway, but did not impede their journey.

Among the throngs hiking into the center of the city was Roger Pineda, a 16-year-old Honduran. "I just want to find some food and a place to sleep," he said, explaining he joined the caravan last week with five family members and a group of friends from the violent city of San Pedro Sula. "I hope Trump allows us to make it to the other side," he said.

In Guatemala, local media reported that around 1,000 migrants were traveling north en route to the Mexican border.

A large column of people marched under a burning sun Sunday as a military helicopter circled low overhead. Many migrants said they were fleeing a toxic mix of violence, poverty and corruption in Central America. Most said they felt safer advancing in a large group.

"We're going to make it, we're going to keep moving so long as they don't stop us," said Honduran Jaffe Borjas, 17, marching alongside a childhood friend at the head of the column that stretched far down the highway to the horizon.

Along the route north to Tapachula, about 25 miles northwest of the border, some broke into song. "If you send us back, we will return!" a large crowd shouted in unison. "We are not criminals, we are workers!"

Photos from the scene show the tough conditions migrants are facing on their march northwards. A large number of children are part of the group that is coming up against hostile checkpoints, blisters and exhaustion as they try to reach the U.S. border.