Mexico forces seize huge marijuana haul in Tijuana
Mexican security forces have seized 105 tonnes of marijuana with a street value of at least $340m (£214m) - the biggest such haul in the country in years.
Heavily armed troops and police raided several homes in the city of Tijuana, on the border with the US, exchanging gunfire with suspected traffickers.
The marijuana was found wrapped in some 10,000 packages.
Drug gangs are increasingly producing marijuana in Mexico, rather than smuggling the drug from South America.
"The seizure of these drugs is without precedent in the country," army General Alfonso Duarte told reporters.
The operation began after municipal police came under fire from gunmen in a convoy of vehicles as they were on patrol in Tijuana, which lies just across the border from San Diego, California.
One officer and one suspect were injured in the exchange of fire.
Troops and police sent reinforcements to help and 11 people were arrested, who then led the security forces to several addresses in the city.
The drugs, found in houses and vehicles, were wrapped in differently coloured packages that had markings and pictures on them, including the cartoon character Homer Simpson.
Gen Duarte said the packages were still being counted and weighed and the amount could increase. The marijuana would be incinerated once all packages had been registered, he added.
The general said local gangs had been preparing to smuggle the drugs into the US, but he did not identify the gangs or say where the marijuana had originated.
According to the Mexican authorities, so far this year 115 tonnes of marijuana have been confiscated in the state of Baja California, where Tijuana is located.
The haul in Tijuana came one week after Mexican President Felipe Calderon visited the city and called it a success in his drug war.
More than 28,000 people have died in drug-related violence in Mexico since 2006.
Mexico is the one of the world's largest exporters of marijuana, a drug that generates billions of dollars of revenues for violent drug cartels in the country.
According to the US authorities, marijuana is being increasingly produced in Mexico. The state department's 2010 International Narcotics Control Strategy report says cannabis production increased 35% to 12,000 ha (29,600 acres) from 8,900 ha in 2008 - the highest level since 1992.
The rise in cannabis and also opium poppy cultivation indicates that the drug gangs are aiming to reduce their reliance on foreign suppliers of drugs, the report concluded.