The shipment weighed about 2,900 pounds and originated in Kenya, The New York Times reported.
The recent seizures of large amounts of elephant tusks indicates illegal ivory trade is strong and involves organized criminal gangs, said officials with Traffic, an organization that monitors wildlife trade.
Nearly 40 tons of ivory was seized by customs officials in 2011, up from 10 tons in 2007. Figures for 2012 are not yet available, but seizure reports put it at least 27.5 tons.
"2011 still reigns supreme as the 'annus horribilis,' but last December's Malaysia seizure pushes 2012 into the top four years of highest ivory seizures by weight, indicating the illegal ivory trade is still running rampant," said Tom Milliken, Traffic's elephant expert, in an email.
Conservationists said a growing affluent population in Asia has increased the demand for ivory and other wildlife products.
No arrests were made for Friday's ivory seizure, the Times reported. The address listed for the shipment's destination was fake.
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