It seems that due to the ancient history of this tomb, the wooden beams in the passage have all decayed, making many areas quite fragile.
Even though the tomb robbers dug the passage with great care, it still succumbed to the fate of collapse. In this portion of the passage, several decayed wooden beams suddenly snapped due to the vibrations, causing the wooden support structure to fail and leading to the entire layer of earth and stone above caving in, blocking the passage from the middle.
Looking further inside, at the end of the passage are four linked trap doors, clearly mechanisms. Below each trap door is a pitfall, which is commonplace in many ancient tombs. Usually, poisonous creatures or inverted sharp blades are buried beneath the pits, and sometimes there are mechanisms for arrow showers.
