Officials from the Guatemalan Migration Institute say some 3,000 people have crossed the border without submitting to a Covid-19 test.
Thousands of mostly Honduran migrants bound for the United States have surged across the border into Guatemala, testing the newly reopened frontier that had been shut by the coronavirus pandemic.
Carrying backpacks and plastic bags, the migrants pushed past two lines of Guatemalan soldiers at the Entre Rios border crossing and continued north – defying the risks and restrictions linked to the coronavirus pandemic.
Guatemalan Migration Institute officials said some 3,000 people had crossed the border without submitting to a Covid-19 test, required for foreigners entering the country.
Many were not wearing masks against the spread of infection.
"We're not thinking about the pandemic, it's the last thing on our minds," said 20-year-old Jefrey Amaya, part of a group of young people from El Negrito, in Honduras' Yoro department.
Amaya said he had joined the caravan after seeing a message on social media.
Soldiers handed out water to passing migrants, some of whom applauded the troops for allowing them to pass.
Dozens of migrants hitched a ride on the back of a large flatbed truck as they headed toward Mexico.
President orders capture of migrants
Guatemalan President Alejandro Giammattei ordered the detention of thousands of migrants.
"At this moment the order has been issued to detain in Guatemalan territory all of those [Hondurans] who have entered the country illegally," Giammattei said in an address to the nation.
Giammattei said that the migrants would be returned to the border and handed over to Honduran authorities.
He urged the migrants "to please return" voluntarily to their country.
"Amid the current health emergency, not only did they fail to respect measures to enter the country but also health measures established to protect our citizens," he said.
Giammattei accused the migrants of arriving with unaccompanied children, and of using women and the elderly as human shields.
In recent years, thousands of Central American migrants travelling in large groups have crossed into Mexico, with the aim of reaching the US border.
The caravan is headed north just a month before the US presidential election, in which President Donald Trump – whose hard line against migrants is a central plank of his policy platform – is seeking a second term.
Trump has threatened Mexico with steep US tariffs if it does not do more to stop a surge of undocumented migrants, and President Andres Manuel Lopez Obrador has since deployed some 26,000 troops to the country's borders in response.
Trump's administration on Thursday announced the US will admit a record low of 15,000 refugees in the coming year.
His Democratic rival in the November 3 election, Joe Biden, has pledged to raise the refugee cap to 125,000, saying that welcoming the persecuted is in line with US values.
The latest migrant caravan set off on Wednesday night from Honduras' second city San Pedro Sula.
Honduran Red Cross officials said 1,200 people left in a first group, joined a few hours later by around 2,000 more, walking north to the Guatemalan border.
Guatemala opened its borders last week after a six-month closure to prevent the spread of the coronavirus, which has hit Central American countries hard.
Some of the migrants said they recognised the risks of catching the coronavirus while on the move, but were prepared to take the risk to escape from high levels of poverty and violence in Honduras.
Monica Toruno, 36, had joined the caravan with her wheelchair-bound six-year-old son and a niece. She said she was forced to leave Honduras because of unemployment and violence.
"I never thought I would subject my son to this, but I lost my job because of the coronavirus, and I'm afraid of staying," Toruno said.
"We are going in search of the American dream, no one will stop us. Either we die here from Covid-19 or we die of hunger. Governments are doing nothing to create jobs," another migrant, 27-year-old Miguel Artiga said.
The vast majority of the migrants on the move are young men. Few women and children were seen.
According to the government of Honduran President Juan Orlando Hernandez, 31,022 Hondurans have been deported back to their home country as of last week, most of them from Mexico and the United States, with the remainder from Guatemala.