Thousands of people were evacuated from several high-rise apartment buildings in Tianjin in recent days after land collapses created large cracks on nearby streets, according to state media and the local government.
Large fissures appeared on roads near a residential complex in Tianjin's Jinnan district and geological experts said they were likely caused by underground cavities below a depth of 1,300 m, the Tianjin government said on Thursday on social media.
As of June 3, a total of 3,899 residents from at least three 25-storey high-rise buildings were evacuated to nearby hotels, state-backed Global Times quoted the district government as saying.
The Tianjin government called the incident a "sudden geological disaster" following preliminary information from geological experts and several government departments after they did surveying, mapping and monitoring at the site.
It cannot be ruled out that the drilling of geothermal wells had resulted in soil loss and land subsidence in the area, the Tianjin government said.
