QUITO — Stashes of cocaine kept in boats and dinghies in the remote Galápagos Islands. Dozens of operatives transporting narcotics on rivers across the border into Colombia. Over the past three years, powerful Mexican drug cartels have systematically moved supplies and operations into Ecuador.

According to Quito-based daily El Comercio, at least four Mexican cartels have operated relatively freely in this South American country, sandwiched between the Andes and the Pacific Ocean, for several years, developing it into a regional logistics hub.

A report released this year by the Mexican Interior Ministry shows a vast network of financiers, security operatives, and traffickers employed by Mexican cartels to conduct their business in Ecuador. The Sinaloa Cartel, formerly led by Joaquín "El Chapo" Guzmán, now imprisoned, was the first cartel to establish roots in the country. They were soon followed by the Zetas, Familia Michoacana, and the Gulf cartel, all among the most powerful criminal organizations in Mexico.

We are used as a hub for organizing and moving drug shipments.

Cocaine, heroin and methamphetamine are the most widely trafficked drugs, and security agents have discovered a supply chain that links various points throughout the country. Narcotics are moved in boats from the Galápagos Islands to ports along the coastline, including Guayaquil, the country's largest city, before being moved in barges along Ecuador's many rivers to the border with Colombia. Once across the border, Mexican traffickers rely on their strong links to cartels in Colombia, where the transshipment continues.

Unlike its neighbors, Ecuador is not an important producer of coca leaf, from which cocaine is refined and produced. The country instead acts as a logistics center. "We aren't a cocaine producing country, we are used as a hub for organizing and moving drug shipments," Ecuador's national police chief Ramiro Montilla told El Comercio.

Ecuadorian police and counternarcotics forces have cracked down on the cartels, arresting dozens of operatives and reinforcing controls on key rivers in two provinces. But the authorities say the groups have become more brazen in their operations in recent years. In 2015, seven Mexicans were arrested on a small northern airstrip as they attempted to fly a small plane loaded with half a ton of cocaine to the United States.

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