A woman in Northwest China owned 41 apartments in Beijing, 10 of which she illegally bought using a fake identity, Beijing police said.

Gong Aiai, 49, a former deputy chief of Shenmu Rural Commercial Bank in Yulin, Shaanxi province, owned 41 houses with a total area of 9,666.6 square meters, the Beijing Public Security Bureau said in an announcement on its micro blog on Thursday.

Previous investigations show that Gong also owned two houses with a total area of 400 sq m in Xi'an, capital of Shaanxi province, and two others covering 600 sq m in Shenmu.

Gong was nicknamed "House Sister" by netizens after an online post in January accused her of buying more than 20 houses in Beijing with fake identities.

The post also said that she had four hukou － one in Beijing, two in Shanxi province and one in Shaanxi.

Hukou is a permanent residence registration and personal identification system. A person can have only one identity card and one hukou.

Beijing police found that with her illegally registered identity and hukou, Gong bought an Audi car and 10 houses with a total area of 1,945 sq m in Beijing. Police did not say whether Gong used her real identity to purchase the other 31 properties.

Police have already seized the properties that Gong bought using a fake identity and hukou in Beijing, according to the announcement.

Her illegally registered hukou in Beijing was revoked on Jan 24.

Gong claimed on Jan 18 that she quit her bank post and started helping her family with their businesses. She said that the houses were purchased with her legal income, according to a report by the Xinhua News Agency.

Yu Qingcai, chairman of the bank, said Gong tendered her resignation in June and has not been to the bank since, but the bank approved her resignation on Jan 2 only after the online post appeared.

A publicity official at Shenmu county government said that authorities have not been able to contact Gong.

Beijing police have detained four suspects, including a policeman, on suspicion of forging official documents and certificates. Three other policemen in Shanxi and Shaanxi have also been taken into custody for helping Gong obtain a fake identity.

Chen Tao, a lawyer and member of the Beijing Lawyers Association, said that even if Gong proves she bought the properties with a legal income, she could still be charged for forging an identity and hukou.

If Gong is convicted, she could face two to seven years in prison, Chen said.

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