The United States said Tuesday it would expand an inter-agency effort to combat human trafficking to the dangerous Darien Gap, the dense jungle on the Colombia-Panama border traversed by many U.S.-bound migrants.

The U.S. Justice and Homeland Security Departments announced both countries would be added to their Joint Task Force Alpha, a specialized unit created in June 2021 to investigate and prosecute people smugglers.

Previously, the task force worked in Mexico and three central American countries – El Salvador, Guatemala and Honduras.

"We are expanding our enforcement efforts to the Darien – among the most dangerous migrant crossings on Earth – and deploying rewards programs like the ones that have brought down drug kingpins to pursue human smugglers," Deputy Attorney General Lisa Monaco said in a statement.

"To those who traffic human beings through the Darien, know this: the full force of the U.S. government is coming for you."

At the same time, the State Department announced it was offering $8 million in rewards for any information leading to the capture or disruption of human trafficking networks operated by the Gulf Clan.

Migrants crossing the Darien Gap face treacherous terrain, wild animals and violent criminal gangs that extort, kidnap and abuse them.

In recent years, many of them have come from South America, trying to cross Central America into Mexico, with the United States as their final destination.

Last month, the United Nations Children's Fund (UNICEF) said that more than 30,000 migrant children had been through the crossing in the first four months of 2024 – a 40-percent increase compared with the same period last year.

Some 2.8 million undocumented migrants enter the United States each year.

As the U.S. election campaign gathers speed, immigration has emerged as a key issue in the race between Democratic President Joe Biden and presumptive Republican challenger Donald Trump.

The former president accuses Biden of allowing an "invasion" at the U.S.-Mexico border and has vowed a mass deportation effort if sent back to the White House.

Biden, seeking to neutralize Republican attacks, recently issued an executive order that would bar migrants who enter the U.S. illegally from claiming asylum when numbers surge past 2,500 in a day.