According to the Tucson Sector of the U.S. Border Patrol, its agents have encountered and closed 113 illicit cross-border tunnels in the Nogales-area Border Patrol Station. A large portion of these tunnels have been found in downtown Nogales, within a 1-mile radius of the DeConcini land crossing.

“One day we got a call (from the police) at 3 in the morning saying we needed to come and check out our property because there was a tunnel coming across from Mexico that had been built in our house,” said Eugenio Celaya, a resident of Nogales.

His house on International Boulevard stands about 50 feet from the border. The imposing 18-foot steel bollard wall draped in concertina wire – which separates his American neighborhood from downtown Nogales, Sonora in Mexico – wasn’t always there.

“Concertina wire was placed along the fencing within the last year by Department of Defense personnel,” Tucson Sector Border Patrol’s Public Affairs Office said in a statement. “This additional wire was at the request of Department of Homeland Security management to reduce incursions along the most vulnerable crossing areas.”

The fence’s previous incarnations included metal planks that could be climbed over, and before that a chain-link fence. That, coupled with portions of dirt road that soak up moisture from rain, paved the way for Mexican smugglers to burrow under the border.

Police came to Celeya’s house to assist the Border Patrol tracking a group of migrants. The tunnel started a few feet into Mexico and came up under Celaya’s stove.

“It was a little thing, maybe 3 feet by 3. … People had to squeeze in real tight,” said Celaya, who had been renting the home out while himself living in Phoenix.

In working with authorities to fill out the tunnel, his family learned that an underground river once ran through the area, so the soil wasn’t too difficult to dig.

The tunnel was taken care of and a for-rent sign went up again on the property. New tenants were screened and a new family moved in. Less than three months later, authorities called on the Celaya family again.

“They reopened the tunnel on the other side and this time it came out underneath our deck,” Celaya said. “They just bypassed the cement and made a new exit.”

The homeowner showed BorderReport.com a large square covered with heavy rock in his front porch where the deck used to be.

“We filled it with concrete and put the rocks on top for good measure,” he said.

Celaya talked to his mother about the perils of renting to strangers and decided to move into the house himself.

“We had been renting the house for about 10 years and I’d come down every month to repair it because people just don’t take care of things. … I decided to move back,” he said.

Other residents of International Boulevard also recall the tunnels. A man approached Tuesday night by BorderReport.com’s tour truck said he knew of up to six tunnels discovered previously in the area.

“Yes, we had many tunnels at one time and people crossed and brought things over. But we haven’t heard of new tunnels lately,” said Armando Robles, a lifelong resident of the area.

BorderReport.com reached out to the Tucson Sector of the U.S. Border Patrol for comment on the tunnels and on what appeared to be an open gate on the border fence on a hill next to a ravine east of downtown Nogales.

“Infrastructure along the border is complex and some areas require special panels. Low water crossings and International Boundary markers require periodic maintenance from United States personnel and may require openings or gates to be placed for temporary access or to allow water flow,” Tucson Sector Border Patrol’s Public Affairs Office said in a statement.

The Santa Cruz County Sheriff confirmed that the chain-link fence was replaced in 1994, and that the metal plank that obscured activity on the Mexican side and could be climbed over was replaced in 2011.

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