Twenty-three of the 30 undocumented immigrants caught by a hidden tunnel spanning the U.S.-Mexico border were Chinese nationals, confirmed U.S. Border Patrol.
In order to get smuggled into San Diego, Chinese nationals have to pay up to $50,000, explained Officer Tekae Michael, from the U.S. Border Patrol San Diego Sector.
“Intelligence has shown for San Diego specific, with Chinese nationals it can go up anywhere from up to $50,000," said Michael.
U.S. Border Patrol agents said 22 of the Chinese immigrants are from the Fugian Province and one is from the Guandong Province. They range in age from 17 to 46.
Hidden Border Tunnel Found at Otay Mesa Crossing
The large group was found around 1:30 a.m. Saturday near the Otay Mesa Port of Entry in south San Diego County, near the border crossing bridge off Britannia Boulevard and Otay Pacific Drive.
In this case, the group realized they were discovered right after they were smuggled into the country, according to U.S. Border Patrol. Once they realized this, they tried to run back into the tunnel. That allowed agents to see the underground passage.
Most people associate the border tunnels with narcotics smuggling. But agents told NBC 7 that it's not uncommon for them to be used for people as well.
“All the cartels own parts of the border. Each differently," said Michael. "So who's smuggling who at any point in time -- each section is owned by a different cartel."
On Monday afternoon, agents worked to seal off the tunnel, located just off Drucker Lane near the Otay Mesa Port of Entry.
Officer Michael told NBC 7 they found five tunnels in various stages of completion so far this year.
Currently, the Chinese nationals discovered at the tunnel are in border patrol custody. After they are processed, they will be moved to a holding facility as their case moves forward.
[DONT CHANGE MAIN HEADLINE] San Diego's Border Busts
According to investigators, the tunnel began in a building on Calle Mar Barmejo in the Garita de Otay area in Tijuana, approximately 328 feet south of the U.S.-Mexico border in San Diego and three miles from the border crossing bridge.
Mexican authorities are working the investigation on that side, at the building, trying to determine who is responsible for the build-out and operation of the smuggling tunnel.
Customs and Border Patrol officials told NBC 7 in the last two years there has been an uptick in nationals from countries other than Mexico trying to enter the country illegally.