MEXICO CITY — Hundreds more Hondurans have joined a caravan of migrants moving toward the country’s border with Guatemala in a desperate attempt to flee poverty and seek new lives in the United States.

Dunia Montoya, a volunteer assisting the migrants, said Sunday that the group had grown to an estimated 1,600 people from an initial 160 who first gathered early Friday in a northern Honduras city.

Caravan participants planned to spend Sunday night at a community center in the town of Ocotepeque before attempting to cross into Guatemala on Monday.

Montoya said many in the group might not be allowed to enter Guatemala because they lack official identification documents.

The migration began to swell after local media coverage of the initial group whose members had agreed to depart together Friday from a bus station in San Pedro Sula, one of the most dangerous cities in Honduras.

Hundreds more soon joined the ranks, wagering a mass exit could improve their chances for getting over borders. Many had already planned to leave Honduras and also felt traveling in numbers could lessen chances of falling victim to robbery and assault that often plague migrants. Families arrived with infants in their arms and toddlers in strollers. They packed light, most carrying little more than a backpack.

The caravan formed just one day after U.S. Vice President Mike Pence urged the presidents of Honduras, El Salvador and Guatemala to persuade their citizens to stay home.

“Tell your people: Don’t put your families at risk by taking the dangerous journey north to attempt to enter the United States illegally,” said Pence.

U.S. President Donald Trump threatened in April to withdraw foreign aid from Honduras and countries that allowed transit for a similar caravan that set out from the Central American country earlier this year.