I’m sure there’s underground detection techniques that could help locate these tunnels. Wherever there’s a border wall, there’s an adjacent access road. Employ something like GPR (ground penetrating radar) along these roads. I think there’s other techniques if GPR is not sufficient. I bet geologists could name a few. There might also be some type of imaging (perhaps similar to LIDAR) that could reveal underground activity.
If they can find Bin Ladin in a cave, they should be able to find these tunnels and blow them up.
Blow them up, hides included!!!
How about drown the tunnels with explosives.
I’m sure there’s underground detection techniques that could help locate these tunnels. Wherever there’s a border wall, there’s an adjacent access road. Employ something like GPR (ground penetrating radar) along these roads. I think there’s other techniques if GPR is not sufficient. I bet geologists could name a few. There might also be some type of imaging (perhaps similar to LIDAR) that could reveal underground activity.