BOGOTA, July 23, 2009 (AFP) - The Colombian Navy seized 63.5 tonnes of cocaine in the first half of 2009, compared to the 75 tonnes it captured for the whole of last year, navy commander Admiral Guillermo Barrera said Thursday.

At a ceremony marking the navy's 186th anniversary, Barrera said his forces had also eradicated 1,727 hectares (6.7 square miles) of coca, the equivalent of all the crops destroyed in 2008, in just the first half of this year.

The navy has also seized 14 submarines used by drug cartels to transport cocaine, and dismantled hundreds of drug laboratories, Barrera said.

According to the latest report issued by the United Nations Office on Drugs and Crime (UNODC), Colombia remained the world's leading producer of cocaine in 2008.

Despite continuing to top producer rankings, the country has launched massive counternarcotics operations, with support from the United States, and UNODC said production has dropped 28 percent, from 600 to 430 tonnes per year.