Ugandan wildlife officers have seized a huge haul of elephant ivory and pangolin scales, representing the deaths of hundreds of endangered animals, police said Sunday.

Over 700 kilograms of ivory -- worth almost $1.5 million on the black market -- and over two tonnes of pangolin skins were discovered in boxes at Uganda's main airport Entebbe, which had been due to be exported to Amsterdam.

The scaly-skinned pangolin is used in traditional medicine in China, with exploding demand in Asia making it one of the most trafficked mammals in the world.

Uganda Wildlife Authority spokesman Jossy Muhangi told AFP that the haul was found in three boxes.

"One box had 76 tusks, another had 61 pieces of ivory mixed with pangolin scales, and the third box had purely pangolin scales," he said.

The tusks, which appeared to be have been recently hacked from elephants, were cut into several pieces, and it was not clear how many animals had been killed for them.

"The tusks were still raw as they were cut from the elephants, but were cut into pieces by smugglers for easy shipment," Muhangi added.

Raw ivory sells for around $2,100 a kilo at markets in China, according to Save the Elephants.

The boxes had been labelled as communications equipment that needed repairs in Amsterdam, and had been cleared for export by custom officials.

They had said the boxes were too heavy to be scanned by X-ray machines, but wildlife surveillance teams insisted they must be searched.

"It was after opening the boxes that we discovered they were wildlife pieces," aviation police chief Ludovic Awita told AFP, adding that three people including the clerk at the airport, a customs officer and the driver of a truck that delivered the cargo have been arrested.

Last week Uganda's environment ministry cancelled a licence that had been given illegally to a dealer to ship a consignment of pangolin scales estimated to be worth some $1.5 million.

In November, Uganda's found that its store of more than a tonne of seized ivory -- worth over a million dollars -- had vanished from government strongrooms.

Poaching has risen sharply across Africa in recent years fuelled by rising demand in Asia for products coveted as a traditional medicine and or as status symbols.

Uganda is a key transit country for the illegal trade in ivory, especially from Congo's huge central African forests.