The fire erupted on the left side of the shooting range of the Chulachomklao Royal Military Academy near the site of the wildfire, which occurred on March 29.
Firefighters are making firebreak to prevent the blaze from spreading to the world heritage site in Khao Yai.
The Royal Thai Army dispatched a helicopter to survey the area and to assess the situation. Meanwhile, 25 firefighters and 15 soldiers are entering the area on foot for the fire-fighting operation. (TNA)