Reports indicate that Mexican drug groups are dispatching some of their most trusted agents to live and work deep inside the United States.
The emboldened presence that experts believe is meant to tighten their grip on the world's most lucrative narcotics market and maximize profits.
Authorities said that if these cartels are left unchecked they will move into the American interior and pave the way for their agents to expand into other criminal enterprises such as prostitution, kidnapping-and-extortion rackets and money laundering.
According to the New York Daily News, cartel activity, starting in the 1990s, the ruthless syndicates became the nation's No. 1 supplier of illegal drugs, using unaffiliated middlemen to smuggle cocaine, marijuana and heroin beyond the border or even to grow pot here.
But a wide-ranging review by an international news agency of federal court cases and government drug-enforcement data, plus interviews with many top law enforcement officials, indicate the groups have begun deploying agents from their inner circles to the U.S.
Cartel operatives are suspected of running drug-distribution networks in at least nine non-border states, often in middle-class suburbs in the Midwest, South and Northeast.
To help fight the syndicates, Chicago recently opened a first-of-its-kind facility at a secret location where 70 federal agents work side-by-side with police and prosecutors.
Their primary focus is the point of contact between suburban-based cartel operatives and city street gangs who act as retail salesmen.
That is when both sides are most vulnerable to detection, when they are most likely to meet in the open or use cell phones that can be wiretapped.
In Mexico, the cartels are known for a staggering number of killings, more than 50,000, according to one tally. Beheadings are sometimes a signature, the report added.