Thai authorities have seized 422 elephant tusk pieces and arrested a Gambian man suspected of smuggling the ivory into Bangkok's main airport.
The tusks were hidden in a shipment listed as unprocessed gemstones, customs department director-general Kulit Sombatsiri said.
He said the parcel was examined because items from Malawi are regarded as high-risk for smuggled goods, and an ivory seizure last year had involved tusks from Mozambique which were similarly concealed.
Mr Kulit said the seizure of 33kg (726lbs) of smuggled ivory worth around £390,000 was the first in Thailand this year.
Thai customs officials last year confiscated more than 1,200 kilograms (2,640lbs) of ivory in nine separate cases.