the tunnel was discovered thursday .
( photo : immigration and customs enforcement ( ice ) via ap ) two more suspected drug - smuggling tunnels linking warehouses in tijuana and san diego have been uncovered by u.s. and mexican authorities , and a 73 - year - old california woman is accused of being the logistics manager for one passageway .
on thursday , they found a second tunnel , which is one longer and more sophisticated than the first .
wednesday , the ice agents uncover one of two tunnels on the u.s. side of the border with mexico this week .
story : major drug - smuggling tunnel found between tijuana the first tunnel found this week was found tuesday in an industrial park in the otay mesa section of san diego .
the two tunnel discovered this week mark the sixth and seven cross - border passages that authorities have located in the last four years .
the busts “ eliminated a multi - million dollar drug smuggling venture and have reduced it to nothing more than a colossal waste of money on the part of the drug cartels , " said william sherman , the drug enforcement administration 's san diego special agent in charge , in a statement . "
on wednesday , ice officials arrested a 73 - year - old chula vista woman on suspicion of overseeing the operation of an underground tunnel leading under the border to an otay mesa industrial park in san diego .
this image shows an agent examining one of two tunnels discovered april 1 , 2014 in san diego 's otay mesa industrial park .