The 832 pieces of ivory, estimated to be worth up to $6.7 million, were apparently heading for the Kenyan port of Mombasa, the Uganda Wildlife Association said.
There is a huge demand in Asia for African ivory for use in ornaments, and experts say some of the seized ivory is believed to have come from elephants poached outside Uganda, with the country increasingly being used as a transit point by poachers in South Sudan or the Democratic Republic of Congo.
The rate of elephant poaching is relatively low inside Uganda, with just an estimated 20 elephants killed for their ivory across the country in 2010, a UWA official told the BBC.
The Convention on International Trade in Endangered Species banned the trade in ivory in 1989, but poaching by criminal gangs slaughtering elephants for ivory has increased across sub-Saharan Africa in recent years, intended for markets in Asia.
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