Updated Jul 13, 2012 - 5:10 pm
Unfinished border tunnel found near Nogales
NOGALES, Ariz. - Federal authorities have unearthed an unfinished border tunnel near Nogales making it the fourth tunnel found in a week.
U.S. Immigration and Customs Enforcement spokeswoman Amber Cargile said the Homeland Security Investigations-led Nogales Tunnel Task Force found the incomplete tunnel on Friday and it didn't appear to be in use. Authorities believe the tunnel's aim was to smuggle drugs into the U.S.
The tunnel's entrance was located on a storm drain wall on the Mexican side of the border, was blocked by rocks. The tunnel runs parallel to a storm drain pipe.
"Where they found the entrance to the drug tunnel was located on a wall that was almost directly beneath the border -- just a little bit off," said Cargile. "It ran four feet in length, so it just barely extended a couple of feet under the United States."
Tunnel construction materials -- ventilation tubing, knee pads and gloves -- were found in the drainage system.
Earlier this week, federal officials found three sophisticated drug smuggling tunnels equipped with lighting and ventilation. Two were found in the San Diego-Tijuana area, and another was found in a vacant strip mall storefront in the southwestern Arizona city of San Luis.
Cargile said the investigation into the Nogales tunnel was ongoing. No arrests have been made.
KTAR's Martha Maurer contributed to this report.