BANGKOK (AP) — Three trafficked Sumatran orangutans were sent back from Thailand to Indonesia on Thursday as part of a joint effort between the countries to tackle the illegal wildlife trade.

Nobita and Shizuka, both 7 years old, and Brian, 5 years old, had been living at a wildlife sanctuary in the western Thai province of Ratchaburi. After the repatriation, there are no more trafficked orangutans currently under the care of Thai authorities, officials said.

Rachmat Budiman, Indonesia’s Ambassador to Thailand, thanked the authorities in both countries for the repatriation and said he has “mixed feelings” about it: happy the orangutans will be back in their natural habitat but sad for the Thai caretakers who had bonded with the animals over several years.

The orangutans were transported from the sanctuary to Bangkok’s Suvarnabhumi International Airport before being put on a plane to Jakarta. Thai officials said Indonesia covers the cost for transportation and the animals’ health examinations.

They will be sent to a rehabilitation center in Sumatra before being released into their natural habitat, Rachtmat said.

The repatriation is “important” because it shows the two countries’ commitment to collaborate in the fight against the illicit wildlife trade, said Athapol Charoenchansa, Thailand’s director-general of the Department of National Parks, Wildlife and Plant Conservation. He said he hoped it would raise awareness about wildlife conservation in the region.

Thai and Indonesian officials fed the animals bananas and dragon fruit while they were being displayed inside their crates at the Bangkok airport before they were taken onto the plane.

In 2016, Nobita and Shizuka were just months old when they were found during a sting operation in Bangkok by wildlife officials, who had agreed to buy the pair online for $20,000. The then-baby orangutans, named after characters from the popular Japanese cartoon Doraemon, were put into a basket in the back of a taxi, and photos of them hugging each other tightly in the basket went viral at the time.

Brian, another male orangutan, was rescued from traffickers and sent to Thai wildlife officials in 2019.

Thailand has sent 74 orangutans back to Indonesia since 2006 in six batches, including the three on Thursday. In 2020, two orangutans named Ung-Ing and Natalie were repatriated.

The Convention on International Trade in Endangered Species — CITES — prohibits international trade in orangutans. They are found only in the forests of Sumatra and Borneo but their habitat is shrinking due to the growth of agricultural land use, making them more vulnerable to poaching. The International Union for Conservation of Nature, the global authority on the status of the natural world, lists orangutans as critically endangered.

Orangutans are often sold into the pet trade and for display in zoos and other attractions.