Seven boxes of ammunition were found after the rampage in a black bag discovered in a dry river bed in Loughner's neighborhood.

CNN: STORY HIGHLIGHTS

The tunnels merge and separate, feed into the sewer system, and branch out again for hundreds of metres, emerging right outside town, amid the bushes of a dry river bed.

BBC: 'Ndrangheta: Exploring the mafia's underground world

These few survivors, she explains, follow the fish in the dry season to deep pools in the bed of the river near Kratie, in Cambodia.

ECONOMIST: The Mekong river