China has resolved 9,029 cases of fraud, illegal land seizures and other violations in the real estate industry since last March, some involving local officials, the Ministry of Construction said on Wednesday.
In some cases, developers had seized land illegally or held sites idle for two years or longer, the ministry said.
China's State Council, the cabinet, recently issued a circular calling for higher land use efficiency.
"If land approved for development remains unused for more than two years, it should be recovered by the government according to laws and regulations. If the land remains idle for more than one year and less than two years, land developers should pay a 20 percent fee," the circular said.
Some developers had built residences without permits, pre-sold substandard apartments or misled buyers with false advertising, the ministry said.
Some local administrative officials were involved, mostly abusing their licensing or supervisory power in return for illegal gains, which took various forms.
"Some didn't impose penalties required by laws and regulations, while some illegally issued planning, construction, pre-sale or demolition permits to developers," the ministry said.
"Some cases involved power-for-money deals between property companies and officials from supervision departments," it said.
The ministry started a crackdown on the real estate sector last March, after it declared that the industry had become a hotbed of corruption.
"The industry suffers institutional loopholes in preventing and combating corruption, especially collusion between government officials and businesses," said Construction Minister Wang Guangtao at a conference last February.
The ministry later pledged to audit developers and inspect all property projects under construction. The ministry has also said it would strengthen cooperation with the discipline, supervision and prosecution departments and raise penalties, especially to those officials who take bribes.