U.S. and Mexican law enforcement agents executing simultaneous raids discovered a recently completed smuggling tunnel linking the two countries, officials said Friday.
The entrances to the tunnel, described as a sophisticated passageway its builders planned to use to smuggle drugs, were discovered in a home in Nogales, Ariz., and an apartment in Nogales, Mexico, according to U.S. Immigration and Customs Enforcement officials.
Five people were arrested during the raid on the Mexican location. No arrests had yet been made on the U.S. side of the border.
The investigation has been under way since April, said Ramona Sanchez, a U.S. Drug Enforcement Administration spokeswoman. The tunnel was about 3 feet wide and 100 yards long, she said.
"It had not yet been used for the intended purpose," Sanchez said.
Agents who served a search warrant late Thursday at the tiny, one-story home found the tunnel entrance hidden beneath plywood sheets weighted down with bags of dirt inside a utility room. The tunnel itself was reinforced in areas with wooden supports and sand bags and had a lighting system, but no ventilation.
The home was largely unfurnished, and searchers found picks, a jackhammer and other excavation equipment.
The tunnel was the largest discovered along the U.S.-Mexico border since January 2006, when a tunnel extending nearly a half-mile from San Diego to Tijuana was found.
Federal officials said the tunnel discovered Thursday has been temporarily sealed and will be filled in after the investigation is complete.
Federal officials said 40 tunnels have been discovered crossing the U.S.-Mexico border in Arizona and California since surveillance was increased following the Sept. 11, 2001, attacks.