Finance Minister Hong Nam-ki said a government investigation has uncovered false reporting of real estate transactions to manipulate housing prices.
Hong announced the investigation outcome during a meeting with officials on Wednesday.
The government has been clamping down on four types of market disruption, including illegal use of insider information, price manipulation and disruption through fake dealings, and illegal reselling of apartment units acquired through subscription.
Some of the cases involved realtors raising prices through feigned transactions between family members. Others involved employees of sales companies raising prices of apartment units owned by the company through false dealings.
With the Land Ministry soon expected to announce further details and the government's countermeasures, the minister pledged to promptly launch a criminal investigation, expose tax defrauders and impose penalties.