US-Mexico border tunnel nets 40 tons of pot

Doug Coleman, special agent in charge with the U.S. Drug Enforcement Administration in Arizona, talks inside a warehouse in San Luis, Ariz., where a drug tunnel was found leading from San Luis, to Rio Colorado, Mexico, on Thursday. Coleman is motioning to wooden boxes that were made specially to load dirt from the tunnel for removal from the warehouse on pallets. In the background is a van used by the builders of the tunnel. Two drug-smuggling tunnels outfitted with lighting and ventilation systems were discovered along the U.S.-Mexico border, the latest signs that cartels are building sophisticated passages to escape heightened surveillance on land. (AP/The Yuma Sun, Randy Hoeft)

The Mexican army says it seized more than 40 tons of marijuana at the entry to a secret tunnel that crossed the border to the United States but didn't have an exit on American soil.

The army said the tunnel found Thursday in Tijuana extended nearly 400 yards — including more than 100 yards into San Diego. It began in a warehouse where soldiers found a trailer filled with dirt, shovels, drills and other equipment.

The tunnel was lit, ventilated and equipped with a rail system.

It was the second, major incomplete tunnel found on the San Diego-Tijuana area in two days and the third along the U.S.-Mexico border in a week.

A completed tunnel was discovered Saturday in a strip mall storefront in the Arizona city of San Luis.