A drug-smuggling tunnel between Sonora, Mexico and Arizona has been discovered by Mexican authorities, the Associated Press reported.
Mexico's defense secretary General Raul Guereca said Saturday that the tunnel was 4.25 feet high and reached a depth of almost 60 feet below ground, and linked facilities in San Luis Rio Colorado, Sonora and San Luis, Arizona, according to the AP.
According to BBC News, the tunnel is the 22nd of its kind to be discovered in three years, and have become more popular as the United States has tightened its border operations, the AP reported.
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The tunnel was fitted with "upgrades" including ventilation, electric lights, and "wagons so your arms don't get tired from carrying all those drugs," the Atlantic Wire reported.
It is still unclear who was responsible for the tunnel's construction, according to the Telegraph, which has video of the tunnel: