Federal, state and county law enforcers have eradicated more than $1 billion worth of marijuana plants from a rather unexpected location in California: the Sequoia National Forest, CNN reported Aug. 8.

U.S. anti-drug officials report that the growing operations are conducted by illegal immigrants with ties to Mexico's drug cartels, and they say these are not small-time operations. "This is about serious criminal organizations," said White House Office of National Drug Control Policy (ONDCP) director John Walters. "They're willing to kill anybody who gets in their way."

Government officials reported that under an eradication campaign called Operation LOCCUST, they were able to destroy 420,000 marijuana plants in eight days. Most of the growing locations in the national forest are several hours from the nearest road and nowhere near the giant sequoias that are the park's signature attraction.

With border enforcement activity making it increasingly difficult to smuggle drugs from Mexico to the U.S., Mexican cartels are turning to U.S. growing operations in which family members or trusted friends are hired to maintain production across the border, government officials in the U.S. said.

The enforcement operations in California include removing complex irrigation systems for the plants, eradicating the plants themselves, and then going after the workers. Thirty-eight arrests have occurred under Operation LOCCUST, along with 29 weapons seizures.