Mexico's Navy on Friday destroyed about 7.6 tons of marijuana at its base in Guaymas, a port town in its Pacific coast state Sonora, the Navy said in a statement.

The drug were seized during anti-drug trafficking operations during the past three months.

Fighting drug smuggling has been one of the key tasks of the administration of President Felipe Calderon since his inauguration in 2006. At least 28,000 people have been killed in clashes related to drug trafficking, most of them gangsters killed by rival traffickers.

This week saw the massacre of 72 migrants who had been kidnapped and held for ransom by a gang.

Calderon said after the killing that the gangsters were likely turning to more violent trades as the government sealed drug trade routes that run north out of Mexico and into the United States.