Along Chile's desert border with Peru, dozens of undocumented migrants line up under the hot sun to try to seek a way out of the country.

The clock is ticking down to a presidential run-off election on December 14, with far-right candidate Jose Antonio Kast the frontrunner to win the second round of voting against leftist Jeannette Jara.

Kast has vowed to expel hundreds of thousands of undocumented migrants from Chile, prompting residents hailing from Venezuela and other parts of Latin America to seek refuge elsewhere before the crackdown.

"Kast said he was going to remove foreigners who have not been regularized," Milbayajaira Rivas, a 56-year-old nurse originally from Venezuela, told AFP.

Neighboring Peru would be one option, but the Peruvian government on Friday declared a state of emergency along its border with Chile, reinforcing its military surveillance to block migrants seeking to cross into the country.

Hugo de Zela, Peru's foreign minister, said the country was not going to accept any more irregular migrants.

At the Chilean border, Peruvian police officers offer water to the migrants to help them in the desert heat, but refuse to allow them to cross.

"Peru doesn't want any more Venezuelans," Rivas said. "We don't know what we're going to do."

This is not the first time Peru has mobilized its military along the border with Chile -- in April 2023, a state of emergency was enacted for two months in response to the number of undocumented migrants, mostly Venezuelans, crossing the border.

- 'There are children' -

Diego Paco, the regional governor of Chile's border area of Arica, expressed his concern to AFP about the welfare of migrants stranded in the desert.

"Among these 100 people, there are children. There are people who could get sick from how cold it gets at night," he said.

The number of undocumented migrants in Chile has exploded in recent years, rising from an estimated 10,000 in 2018 to around 330,000 by 2024, according to Chile's National Migration Service. The majority of undocumented migrants hail from Venezuela.

Undocumented migrants can access health services in Chile, and enroll their children in public schools.

But some Chilean residents blame the increased number of migrants for a surge in crime, despite Chile remaining one of the safest countries in the region.

"I understand that criminals have come from my country, but so have good people who just want to work," said Billy Gonzalez, a Venezuelan migrant in Chile.

The 48-year-old optical technician expressed frustration at Kast's threats of deportation.

"At least bring us a bus, let everyone pay for their own ticket and take us to Ecuador so we can continue on the route to Venezuela," he said.