Since July, more than 1,600 of the birds, including Bolt, the world's most expensive racing pigeon, bought from the auction house Pigeon Paradise by Chinese buyers have been seized by Chinese customs agents who say the value of the birds was incorrectly reported on import documents and that insufficient duties were paid, Britain's The Independent reported Sunday.
Pigeon Paradise worked with Chinese officials to release 401 birds.
Now, the Belgian Foreign Office is working to free the remaining 1,212 birds, Flanders News in Belgium reported.
Among the impounded birds was the famous racing pigeon Bolt, named after Usain Bolt, purchased in May by a Chinese businessman for a record $419,554.
"A number of these birds are world-class racing pigeons," Joren Vandeweyer of the Foreign Ministry told the Flanders News. "It's up to the Chinese authorities to decide if they want to set the pigeons free again."