China secretly dug a tunnel for four years to expand his ground floor apartment in Shenzhen, causing cracks in the apartment building.

The tunnel, about two meters deep and about 100 square meters, was dug just below Ding's apartment on the ground floor of the apartment building, helping to double the area of the house, Chinese media reported on December 30.

Ding's neighbors say that tunneling causes cracks in the apartment walls and can affect the structure. "Our intestines burn like fire every day while living here," said Wang, a neighbor of Ding.

Wang said Mr. Ding's family ignored the neighbors' complaints and continued digging for 4 years. "They didn't listen and even challenged us to go to court," Wang said.

He Wenjiang, a regional management official, said he had repeatedly checked Ding's apartment, but "they always stopped work when we arrived and built the tunnel slowly, secretly like a cave digging mouse" .

In an interview with local media, Ding's father said that his son did not do anything wrong, because people in the apartment complex where he lived also built many illegal works. "They built it high. So why can't I dig a tunnel? A house even built two floors, I only dug one more floor," he said.

Local authorities said they invited a third party to assess the safety of the building before deciding what to do with Ding's basement and whether to punish the person.

Illegal expansion is common in China, especially in large cities, where house prices have skyrocketed over the past 10 years. A ground house in the capital, Beijing, collapsed after the owner dug a tunnel 18 meters below it, causing the landlord to be sentenced to 5 years in prison.