Fifty-four orangutans illegally smuggled into Thailand to take part in kick-boxing contests are finally to be sent home after two years in government custody.

Thai officials today promised to send the apes back to their native forests as soon as DNA tests confirm exactly where they come from.

The orangutans have been languishing behind bars at the Khao Pratap Chang wildlife preserve ever since they were seized at the Safari World Zoo on the outskirts of Bangkok in 2004, where they had been made to fight each other daily for spectators.

Efforts to send the animals home have been delayed by wrangles over who is responsible for them and where they belong.

The owner of the zoo claimed they had been bred in captivity, but DNA tests eventually proved that 57 of the 114 zoo orangutans were not born in the in-house breeding programme but had apparently come from outside Thailand.

A Thai court ruled earlier this year that the 57 illegally smuggled apes should be sent home. Three of those have died, while the other 57 orangutans have been returned to the zoo after the owners proved that they were bought before Thailand amended its law in 1992 to make smuggling illegal.

Steven Galster, of the WildAid-Thailand conservation group, said today that several orangutan experts had concluded that the 54 apes were from Indonesia’s Kalimantan province.

"I think all or most of them are going to go back to Indonesia, not to Malaysia," said Mr Galster said.

"Most of the experts have taken a look at them, without even doing DNA, and they have said these are from east and west Kalimantan. They can just tell."

Thai, Indonesian and Malaysian authorities will meet on Friday and Saturday in Bangkok to discuss the fate of the orangutans and the results of further DNA tests to determine their country of origin.

"During the meeting we will finally decide which country the 54 orangutans will return to," said Chawann Tunhikorn, the deputy chief of Thai national parks.

"We had already made our decision but we wanted to return them through the proper channels. Thailand has been working closely with the governments of Malaysia and Indonesia to find a proper way and proper procedure to repatriate the orangutans back to their geographical origin. We have no intention of keeping these orangutans."

Orangutans are native to the island of Sumatra in Indonesia and to Borneo, an island shared by Indonesia, Malaysia and Brunei. Their population is in dramatic decline and scientists roughly estimate that 27,000 are left in the wild.

They are considered an endangered species and their trade is banned internationally under the Convention on International Trade in Endangered Species of Flora and Fauna (Cites).

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