The "super tunnels" were the sixth and seventh found between Tijuana and San Diego since 2010. 
 
 This image shows an agent examining one of two tunnels discovered April 1, 2014 in San Diego's Otay Mesa industrial park. The first tunnel, stretching about 600 yards, was discovered on Tuesday. Authorities say it was equipped with lighting, a crude rail system and wooden trusses. The other tunnel was discovered Thursday. It’s described as stretching more than 700 yards and more sophisticated, with an electric rail system and ventilation equipment. (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. 
 
 No drugs or other contraband were found in the so-called super tunnels, which featured lights, rails, wooden supports and ventilation, or in warehouses on either side of the border, U.S. Immigration and Customs Enforcement announced Friday. 
 
 The passages, which U.S. Attorney Laura Duffy said cost millions of dollars to build, were the sixth and seventh super tunnels found between Tijuana and San Diego since 2010. 
 
 STORY: Major drug-smuggling tunnel found between San Diego, Tijuana 
 
 The first tunnel found this week was found Tuesday in an industrial park in the Otay Mesa section of San Diego. About 600 yards long and 70 feet underground, it was detected under the cement floor of a warehouse containing children's toys and TVs. 
 
 Wednesday, the San Diego Tunnel Task Force arrested Glennys Rodriguez, a U.S. citizen from Chula Vista, a San Diego suburb. She is accused of overseeing logistics and faces federal charges of conspiring with others to maintain a drug-involved premises. 
 
 The second, more sophisticated passage was unearthed Thursday in Otay Mesa by Mexican investigators following leads from their U.S. counterparts. Stretching about 700 yards long, it contained a multi-tiered electric rail system, said ICE, which did not indicate the contents of the second warehouse or the warehouses in Tijuana. 
 
 "While technology certainly plays a part in our ongoing efforts, ultimately these investigations often owe more to the powers of observation and old fashioned detective work – and that was exactly what happened here," said said Derek Benner, special agent in charge of Homeland Security Investigations in San Diego. 
 
 In November 2010, border agents uncovered an 1,800-foot-long drug-smuggling super tunnel connecting Tijuana with the same industrial park in San Diego. More than 20 tons of marijuana were seized in the Otay Mesa warehouse; Mexican soldiers confiscated five tons at the other end. 
 
 Since 2006, more than 80 cross-border tunnels in various stages of construction have been found, mostly in California and Arizona. 
 
 Read or Share this story: http://usat.ly/1jLZlfL ||||| ICE agents uncover one of two tunnels on the U.S. side of the border with Mexico this week. The tunnel was hidden in a warehouse and was equipped with a crude rail system. (Immigration and Customs Enforcement / ) 
 
 Just as Immigration and Customs Enforcement agents in San Diego shut the door on their latest drug-smuggling tunnel case, another one opened up. 
 
 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. 
 
 On Thursday, they found a second tunnel, which is one longer and more sophisticated than the first. 
 
 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. 
 
 "Our goal is to not only shut these tunnels down before they become operational, but to ensure that the cartels backing these elaborate smuggling operations are investigated and prosecuted." 
 
 The two tunnel discovered this week mark the sixth and seven cross-border passages that authorities have located in the last four years. Officials have found more than 80 tunnels from California to Arizona since 2006. 
 
 But the quantity of drugs – if any – that were successfully channeled through the tunnels found this week is unknown, authorities said. According to the federal complaint against Glennys Rodriguez of Chula Vista – who is accused of supervising the pathways - the warehouse where the first tunnel was found was purchased last May. 
 
 In their announcement, authorities described the elaborate passage smugglers had carved under the border: 
 
 The first tunnel was approximately 600 yards long, secured with wooden trusses and equipped with lighting and a crude rail system. Its exit on the U.S. side was 70-feet below ground and had a pulley system for hoisting packages to the surface. 
 
 Children’s toys were found strewn in the warehouse where the tunnel lead, officials said. 
 
 Agents have found similar settings outside other tunnels they’ve uncovered. They say operators hire people to occasionally drop by the property to make it appear to be a normal business to neighbors, according to court documents. 
 
 The second tunnel was discovered by Mexican authorities on Thursday. Authorities found that the second tunnel exited just around the corner from the first and was noticeably more advanced. 
 
 The second tunnel was about 700 yards long, had ventilation and a multi-tiered electrical rail system. 
 
 So far, Rodriguez is the only person facing charges, but her criminal complaint names several other people who authorities believe are related to the tunnels, including a man who authorities said has been caught constructing cross-border tunnels before. 
 
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 Joseph.serna@latimes.com 
 
 Twitter: @josephserna
– Federal agents discovered two more major drug tunnels between California and Mexico this week, reports USA Today. Each began under a warehouse in Tijuana and ended under another in San Diego. The discovery holds a lesson for cartels: If you're going to spend millions building these things, you might want to invest in better fronts. Immigration and Customs Enforcement agents found the first one after noting that the US warehouse had nothing but cheap toys inside, as if it were an exporter, the same front used in a tunnel found last year, reports the Union-Tribune. The discovery of the first tunnel led to the discovery of the second one in a nearby warehouse in the same industrial park. Authorities arrested a 73-year-old woman in Chula Vista, California, suspected of supervising the smuggling operations, reports the LA Times. The tunnels were 600 to 700 yards long and were equipped with lighting and rail systems, with one notably more sophisticated than the other. Unlike previous discoveries—these are the sixth and seventh tunnels found between Tijuana and San Diego since 2010—no drugs were found during the raids.