Mexican security troops seized more than 105 tons of marijuana in over 10,000 packs on Monday during a special operation in Tijuana, south of the Mexico-U.S. border.

The seizure, reportedly the largest in years in Mexico, was made as soldiers and policemen raided several houses in suburban Tijuana in the early hours of Monday.

A total of 11 suspected drug traffickers were detained after a brief exchange of fire.

The drugs, estimated to worth at least 4.2 billion pesos (340 million U.S. dollars) in street value, were headed for the U.S. after being brought together in Mexico for several months, officials said.

Mexico is a major transit point for drug trafficking to the United States. Since 2006, the Mexican government has been taking tough measures against the country's notorious drug cartels.