The park's management said Wednesday the cameras have been in position where a local reported seeing a tiger inside the park in the central Quang Binh Province.
When seeing the tiger, the person had freaked out, climbed a tree, and made some sounds to distract the animal, causing it to run away into the forest.
The incident was later reported to the park's management board, the government news portal reported Thursday.
A camera trap is a digital camera connected to an infrared sensor that can "see" warm objects that are moving, like animals. When an animal moves past the sensor it causes the camera to fire, recording an image or video to the memory card for later retrieval.
The trap can be left in the field to continuously monitor an area of habitat for weeks or even months, recording the rarest events that occur in nature, according to the World Wild Fund for Nature (WWF).
According to Save Vietnam's Wildlife, a non-profit organization that works on solutions to conserve Vietnam's wildlife, the last photo of a tiger in the wild in the country was captured in 1998. In the past 24 years, SVW has not seen any signs of tigers in the wild in Vietnam.
Therefore, if it is confirmed that a tiger has really returned to Phong Nha – Ke Bang Park, it will be a "thrilling discovery" for conservationists, it said.
According to the WWF and the International Union for Conservation of Nature, Vietnam had just around five tigers left in the wild as of 2015.
At the Global Tiger Summit in Russia in November 2010, Vietnam and 12 nations with degradation in the number of tigers in the wild had pledged to double the existence of wild tigers in each country by 2022.
The 900-square-kilometer Phong Nha-Ke Bang park is home to over 300 caves and grottoes that date back some 400 million years, including Son Doong, the world’s largest cave.