The 74-year-old driver of a 2-ton-truck that fell into a sinkhole remained missing 10 days after the hole appeared on January 28.

Saitama Prefecture started using a drone to investigate the inside of the hole on February 5.

What is believed to be the driver's seat was found 100 to 200 meters downstream of the sewer pipe from the hole, partially submerged in water.

The white object was made of metal and deformed.

Officials have not been able to find the driver, and they believe that he may have been swept out of the driver's seat.

Officials continued investigating inside the pipe with a drone on February 6.

Workers have been unable to enter the pipe due to the accumulated earth and sand inside the pipe.