Mexican police in Mexicali have recently "recovered a powerful improvised cannon used to hurl packets of marijuana across a border fence into California."
The cannon is "made up of a plastic pipe and a crude metal tank that used compressed air from the engine of an old car," and was able to launch packages stuffed with pot "that weighed as much as 30 pounds," according to police.
U.S. authorities have seen this type of air delivery system. In December of last year, authorities in Yuma, Arizona discovered dozens of canisters of marijuana weighing about two pounds each. They had been launched up to 500 feet by a similar pneumatic cannon rig.