HANOI, Vietnam—A critically endangered turtle that somehow made it to Vietnam decades ago has been returned to its original home: Cambodia.

The mangrove terrapin was handed over to Cambodian authorities in a ceremony in southern Ho Chi Minh City on Friday.

The conservation group Education of Nature Vietnam said the turtle would be introduced into a conservation breeding program in Cambodia.

The turtle was first spotted by ENV staff in 2010 in a park in Ho Chi Minh City.

The park bought the turtle from local people in the 1980s, but the conservation group says it is unclear how the terrapin ended up in Vietnam.