Story highlights Border Patrol: "This is one of our larger cash seizures"

California is a hub for money laundering by Mexican cartels

(CNN) Border Patrol agents in California hit a jackpot this week in terms of cash seizures: $3 million.

For the agency that deals with border security, it was a major intercept of smuggled cash. The Border Patrol noted most of its past seizures have been in smaller amounts: $300,000, $51,000 and $43,000.

"This is one of our larger cash seizures," said Ralph DeSio, spokesman for the San Diego office of US Customs and Border Protection. Normally, he said, the big figure reported is the value of confiscated drugs.

The U.S. Border Patrol photographed the boxes it says carried $3 million in the trunk of a Volkswagen Passat

Currency smuggling and money laundering are the lifeblood for the Mexican cartels moving the majority of heroin, cocaine and methamphetamine across the US border as well as for human traffickers.

If the sophisticated gangs can't get their tens of millions of dollars in cash home each year, the US market wouldn't be nearly as attractive. And California is central to those type of activities, experts say.