Originally published on April 7, 2014

Officials uncovered two drug-smuggling border tunnels running across the U.S.-Mexico border and arrested a 73-year-old woman charged with overseeing their construction, agents for Immigration and Customs Enforcement announced on Friday last week.

The two tunnels discovered last week were the sixth and the seventh to be found in the Otay Mesa area of San Diego in less than four years.

The entrance of the first of the two tunnels, discovered on Tuesday, was found within a warehouse, hidden under boxes of televisions and toys and sealed by a concrete slab. The small entrance opened to a 15-foot walkway, which led to a 70-foot vertical shaft complete with a half-ton winch and pulley system. The tunnel stretches 600 yards long, ending at another warehouse in Tijuana.

A second 700-yard tunnel equipped with a multi-tiered electric rail system and ventilation equipment was discovered on Thursday in the same area.

No drugs were found in the tunnels at the time of their discovery, and agents cannot tell whether the drugs moved through the tunnels before they were discovered.

Arrested on Tuesday, 73-year-old Glennys Rodriguez denied her connection to the warehouse tunnels despite surveillance evidence showing the contrary. According to a complaint filed by the U.S. Attorney's office, Rodriguez paid a friend to lease one of the warehouses under his name while the tunnels were under construction.