Mexico makes its biggest-ever marijuana haul

Mexican soldiers have seized 105 tonnes of marijuana with a US street value of more than $340 million in the country's biggest-ever pot haul.

Heavily armed soldiers raided a series of homes in a poor suburb of Tijuana, across the border from San Diego and came under fire at least once as they took the drugs, also arresting 11 suspected traffickers.

Troops found the narcotics wrapped in 10,000 brown and silver packages in houses and a parked truck. The marijuana was brought together from across Mexico over several months and bound for the United States.

General Alfonso Duarte told reporters at a military base in Tijuana that the seizure was "without precedent" in Mexico.

The marijuana was carefully wrapped and labeled with signs and logos for a series of specific distributors in the United States.

The bust is also good news for President Felipe Calderon, who has staked his reputation on beating back powerful drug cartels in a military-led campaign he launched in December 2006.

Calderon is under pressure to show his drug war is working as the death toll over the past four years climbs to nearly 30,000 people, putting Washington and foreign investors on edge and provoking alarm among many Mexicans.

Mexican cartels have grown extremely powerful over the past decade, while violence sparked by cartel rivalries has spread beyond long-troubled cities such as Tijuana and Ciudad Juarez to formerly peaceful places including the wealthy industrial city of Monterrey and the Caribbean resort of Cancun.

Mexico is one of the world's top marijuana producers, exporting about 7,000 tonnes of the drug a year. Marijuana and home-grown heroin together generate more than $10 billion in exports for the cartels every year, according to private estimates.