Mexican security forces in the city of Tijuana, on the border with the US, have seized 105 tonnes of marijuana - the largest such drug haul for many years.

墨西哥与美国边境城市提华纳城保安部队收缴105吨大麻——这是近几年来收缴数量最多的毒品。

The army said the packages were still being weighed and counted

Eleven people were arrested during the operation, during which one police officer and one suspect were injured in exchanges of gunfire.

The drugs were found wrapped in 10,000 packages, in houses and vehicles.

They have a US street value of more than $340m, the Mexican military said.

"The seizure¹ of these drugs is without precedent²（在前的） in the country," General Alfonso Duarte told reporters.

Soldiers and police found the drugs in pre-dawn raids in three neighbourhoods in Tijuana, a city across the border from San Diego, California.

Gen Duarte said the packages were still being counted and weighed and the amount could increase. The marijuana（大麻） would be incinerated（焚化，烧弃） once all packages had been registered, he added.

The general said local gangs had been preparing to smuggle³ the drugs into the US, but he did not identify the gangs or say where the marijuana originated.

According to the Mexican authorities, 115 tonnes of marijuana had been confiscated⁴（充公，没收） in all of Baja California state so far in 2010.

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.