Border Patrol and a host of other government agencies are investigating after authorities found a cross-border tunnel in the east San Diego County town of Jacumba.
The tunnel was discovered by Mexican State Police on September 19 just 221 feet south of the U.S./Mexico boundary.
On October 4, agents found an entry point that was roughly 31 feet deep. The total length of the tunnel is 627 feet, 336 feet of which is in the United States.
The average length of the tunnel was three feet high and two and a half feet wide. An exit shaft was discovered, but didn't break the surface into the U.S.
On top of the massive tunnel, authorities discovered a complex system used to light and ventilate the tunnel. The system included solar panels used to run the electrical, lighting and ventilation systems, and a pump system used to get rid of any water inside the tunnel.
Authorities didn’t say whether any arrests have been made or what the tunnel was supposed to be used for, though the Drug Enforcement Administration is one of the investigating agencies.