"As efforts to strengthen security on our Southern Border increase, Mexican drug cartels are being forced underground to smuggle their deadly drugs into the United States," he said.
Authorities said the tunnel is about 5 ½ feet tall and 2 feet wide. Its exit was discovered in the warehouse district of Otay Mesa, California, blocked by several hundred sandbags, according to CBP. A separate offshoot of the tunnel extended 3,539 feet from the main passage, but didn’t breach the surface, officials said.
No arrests were immediately made in connection to the discovery. Authorities continue to investigate.
The tunnel is the longest of its kind ever found on the border. Previously, the longest tunnel had been a 2,966-foot one discovered in 2014 in San Diego, according to CBP.