Three members of Britain's Serious Organised Crime Agency (SOCA) met US agents on the Texas-Mexico border this week in a bid to put a stop to cartels taking hold on Britain and Europe.
The British agents spoke about surveillance tactics, special operations teams and cybercrime units, according to a US immigration officials.
On Thursday, they watched how ICE investigators tore apart a car where a cargo of marijuana was found at the Paso del Norte Bridge in this West Texas city.
The agents are expected to head to Miami next week to learn about port operations in the US.
"The most important lesson that we have shared with SOCA, is that if they are not prepared to deal with the Mexican cartels, they will spread like a cancer and will entrench themselves in the economy and community in an attempt to 'legitimise' their illicit profits." Oscar Hagelsieb, an agent at the US Immigration and Customs Enforcement's Homeland Security Investigations office, said. "They must also be aware of the violence that will undoubtedly follow."
US authorities believe Mexico's Sinaloa cartel has drug distribution networks in England and has established footholds in France and the Netherlands, among other places in Europe, he said.
Mexican crime groups have previously made attempts to establish a presence in Europe, Mr Hagelsieb added, "but not to the scope we are seeing now. The Sinaloa is the first cartel that can have an impact worldwide."
SOCA was created in 2006 and is responsible for investigating drug trafficking, criminal organisations, cybercrime, counterfeiting, the use of firearms and serious robberies.
In a statement read by one of the British undercover agents, the agency said it wanted its agents to come to El Paso as "it's always better to be exposed to the problems and the environment first hand."
"We want to learn from the special agents about the local, regional and international impact of the widely reported scale of drug trafficking that takes place across this border," the statement said.
The British agents were also interested in how El Paso has managed to remain one of the safest cities in the US even though it's across the Rio Grande from Ciudad Juarez, a city afflicted by one of the highest murder rates in the hemisphere.
US Immigration and Customs Enforcement's Homeland Security Investigations collaborates with local agencies, targeting specific criminal groups and gathering intelligence on them, Mr Hagelsieb said. "We are able to intercept them at points of entry before they cross back and forth."