Extreme temperatures and getting lost are the two greatest dangers facing thousands of people who each year try to cross into the US illegally over its southern border on long treks led - part of the way, at least - by people-traffickers known as "coyotes."

This is the message being disseminated by the US Border Patrol at a day-long event on Thursday in the border city of Laredo, Texas, to show people what obstacles face undocumented immigrants who try to sneak across the southern US border and the role the federal agency plays in rescuing them.

A guided hike over tracks and trails near the border of 2.5 kilometers (1.5 miles) in temperatures of 30 C (86 F) provided the public with a taste of the experience of migrants who walk for more than three days in summer temps exceeding 45 C (113 F), the assistant Border Patrol chief for the Laredo Sector, Enrique Martinez, told EFE.

"Unfortunately, people who try to enter the US illegally put their lives in the hands of the 'coyotes' and people-trafficking organizations," he said, adding that these criminal groups are only interested in the money they can squeeze out of people desperate to enter the US.

Martinez also said that often the coyotes abandon the migrants without water or food if they cannot keep up with the group or become a burden in some way.

The undocumented migrants, who don't know the territory or the roads along the US-Mexico border, often get lost and wander until they collapse or are rescued by federal authorities.

A group of seven Border Patrol agents simulated the rescue of a migrant who had fallen down a hillside, breaking his ankle.

Under the orders of agent Joshua Priest, the Border Patrol personnel worked in a coordinated way to assist the injured person and get them to safety.

The simulation was designed to represent one of the many activities the Border Patrol engages in besides processing more than a million people who cross legally over the border each year.

Under the auspices of the 1998 Border Security Initiative, the Border Patrol works to prevent deaths and increase rescues of illegal immigrants who are taken advantage of by the coyotes and wind up in dangerous situations, agent Jaime Fierro, said at a press conference.

During the current fiscal year, which began on Oct. 1, 2016, the Border Patrol in the Laredo Sector has made more than 700 rescues on the US side of the border.