A 56-year-old Vietnamese man was arrested on Sunday at Bangkok's main airport after six pieces of horn, weighing about 10.6 kilos, were found in his luggage, authorities said.
The same day in Ho Chi Minh City in southern Vietnam, airport customs officers confiscated six pieces of rhino horn weighing some 16.5 kilos, the state-run Thanh Nien newspaper said.
In that case, a 33-year-old Vietnamese man admitted to smuggling the horn from Mozambique via Doha and Bangkok, it said.
Illegal hunting of rhinos has risen in recent years to meet surging demand for their horns in parts of Asia, in particular Vietnam where they are highly prized for their supposed medicinal qualities.
One hundred grams of Rhino horn costs up to $5,000 on the black market in Vietnam.
It was unclear if there was a link between the two cases.
The suspect detained in Bangkok flew into the country from Ethiopia and was due to board a connecting flight to Hanoi but left his luggage unclaimed on a baggage carousel, said Narongrit Sookprakarn, a wildlife official at Bangkok's Suvarnabhumi airport.
He admitted to carrying the horn from Mozambique, he said.
The man is accused of bringing protected wild animal parts and prohibited goods into the country without permission. If convicted he could face four years in prison and a fine of at least 40,000 baht ($1,300).