Thai customs said on Friday they had seized two tonnes of ivory worth over $3.3 million hidden in a shipment of frozen fish -- equivalent to more than 120 elephants killed.
Officials found 247 tusks concealed among hundreds of boxes of mackerel apparently from Kenya, in a boat at Bangkok Port on the Chao Phraya river, the customs department said.
The haul -- which officials said was the biggest in a year and equated to at least 123 elephants killed -- weighed 2,033 kilos (4,472 pounds) and was displayed by authorities in the Thai capital.
Wildlife anti-trafficking group Freedland said it was the first time customs officials had found ivory coming into Thailand by boat and said it showed smugglers were being forced to change tactics.
"It is another sign that steady collaboration by Thai and African law enforcement is foiling ivory traffickers who are losing huge amounts of money, and that's where you have to hit them to stop them -- in the pocket," said the group's director, Steven Galster.
Freedland said the seizure marked the ninth major enforcement action by authorities in Kenya and Thailand since a collaboration was agreed in November 2010.
More than four tonnes of ivory have been confiscated since then, it said.
International trade in ivory was banned in 1989, but seizures have risen dramatically in the past five years.
Experts say traffickers use Thailand to smuggle ivory, rough or carved, into neighbouring China -- where it is ground up in traditional medicine -- and Japan. But some also ends up in the United States and Europe.
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