The extreme risks and rewards of the drug trade have led to increasingly creative smuggling methods as criminal groups continually look for new ways to evade detection. InSight Crime counts down five of the most inventive alternative drug trafficking methods.
5. Liquid Cocaine
Liquid cocaine is powdered cocaine mixed with a variety of solvents, which can later be separated out at a shipment's final destination. Once in liquid form, the cocaine is often packed into latex capsules and swallowed by drug "mules", sprayed onto clothing, or disguised as legal liquids such as liquor.
This form of cocaine smuggling is notoriously difficult to spot. In Bolivia, for example, authorities reportedly have no way of detecting liquid cocaine and have instead trained anti-drug agents to identify traffickers based on their appearance and behavior.
4. Homemade Submarines
Criminal groups throughout Latin America have been known to build homemade submarines to transport drugs. Confiscated vessels range from small semi-submersibles that travel close to the surface, to fully-submersible vessels that are extremely hard to detect.

3. Catapults and Canons
On multiple occasions, Mexican authorities have confiscated catapults and cannons made from compressed-air guns used by criminals to fire drugs over the US-Mexico border. Smugglers typically use the machines -- which are often made out of cheap and readily available materials -- to launch bales of marijuana.
2. Drones and Ultralight Planes
While authorities in the region have begun using drones to detect and track drug shipments, the same technology has been used by Mexican drug cartels to smuggle narcotics into the United States. Criminal groups have also used ultralight one-person planes to land drugs on US soil.
Both types of aircraft are hard to detect using radar, and drones will likely become more cost-effective for traffickers as the technology advances and is further adopted by legal commercial enterprises.

1. Cocaine Disguised as Coal
Colombian authorities recently seized a shipment of coal in the Caribbean port city of Barranquilla that on closer inspection turned out to be coca base. Smugglers had coated 306 kilos of coca base with fiberglass, then painted the pieces black.
In Peru in August, drug traffickers employed a similar method, although in this case they used real pieces of coal and drilled holes in them, hiding around six tons of cocaine.