A man plummeted 40 feet down a hole while working at a construction site on one of the U.S.-Mexico border wall prototypes in south San Diego County Wednesday, officials confirmed.

U.S. Customs and Border Protection (CBP) spokesperson Carlos Diaz said the worker survived the fall without serious injuries and promptly returned to work at the site in Otay Mesa.

A construction worker fell 40 feet down a hole at the site of a border wall prototype in Otay Mesa Wednesday. Officials said he was not paying attention when he stumbled. He was not hurt and promptly returned to work. NBC 7's Gaby Rodriguez reports.

Diaz said the worker was not following protocol and, as he walked backward at the site, fell into a 40-foot-deep hole around 10 a.m. The worker was not paying attention, said Diaz who classified the incident as a "misstep."

Diaz said the worker was hoisted out of the hole and was evaluated for injuries at the scene. He was not hurt and promptly returned to his duties.

Diaz said workers set up a double layer of plywood at the site to prevent this type of accident from happening again. Officials said the worker was digging the foundation for one of the border wall prototypes at the time of the accident.

Construction worker falls into 40 ft. hole while working on border wall project. He's okay and back at work. #NBC7 — Gaby Rodriguez (@GabyR_news) September 27, 2017

Construction did not pause during Wednesday's incident.



Bulldozers continue flattening out dirt around the area by the corner of Enrico Fermi Drive and Via De La Amistad. Six companies will build eight different prototypes of the border wall proposed by President Donald Trump for the U.S.-Mexico border.

Right now. Border wall prototype construction site. Only 2 of 6 companies are on site. Walls must be complete in 30 days. #nbc7 pic.twitter.com/u6q09Xwgy3 — Artie Ojeda (@ArtieNBCSD) September 27, 2017

Four of those prototypes will be made of concrete and the others of different materials. The wall will be built not far from the current U.S.-Mexico border wall. No other information was immediately available.

A man lost is the desert was rescued by Border Patrol Agents and transported to the El Centro Border Patrol Station for further care and investigation.

At this point, the company that the man works with is unknown.

Diaz said a so-called "emergency protocol" was put into effect following the man's fall, although he couldn't elaborate on details of that process.

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