Kenyan security dogs at Nairobi airport Friday outsmarted traffickers and sniffed through a layer of pepper to uncover a 600-kilo cargo of ivory bound for Nigeria, a statement said.

"Kenya Wildlife Service (KWS) Canine Unit together with Police and Customs officials at Kenya's main airport in Nairobi have intercepted 345 pieces of raw ivory weighing 601 kg destined for Lagos, Nigeria," KWS said.

"The ivory, packed in six crates and sprayed with pepper to prevent dogs from sniffing it, had been further covered with aluminium foil," the wildlife service statement said.

It added that an investigation had been launched to determine who the smugglers were.

The illegal trade in ivory is fuelled by demand in Asia and the Middle East where elephant tusks and rhinoceros horns are used to make ornaments and in traditional medicines.

Africa is home to an estimated 472,000 elephants whose survival is threatened by poaching and illegal trade in game trophies, as well as rising population causing habitat loss.