A former housing administration official whose family once owned 31 houses in Henan province was arrested on suspicion of corruption.

Zhai Zhenfeng, 50, who was director of the housing administration bureau in Erqi district of Zhengzhou, capital of Henan province, was arrested on Sunday night, the people's procuratorate of Zhengzhou announced.

The prosecutor found that Zhai's family once owned as many as 31 houses, of which seven had been sold when the family's assets were exposed by a whistle-blower on the Internet on Dec 26.

The whistle-blower said on his micro blog that Zhai's daughter owns 11 affordable houses and two ID cards. Zhai's daughter, whose homeownership sparked online outrage, was later nicknamed "House Sister" by netizens.

The procuratorate started investigating Zhai on Jan 4 and confirmed some of the charges in the whistle-blowing post online. But it denied the online accusation that the properties in the name of Zhai's daughter were affordable houses.

Zhai ran a real estate company in the name of his brother in law, and his family got 20 houses in a residential community the company developed when it was sold in 2010, of which 11 were in the name of Zhai's daughter.

The other 11 properties owned by Zhai's family were purchased with profits from the family's business, the prosecutor said.

The whistle-blower said that Zhai's family has houses in Beijing and Shanghai, but the prosecutor did not find any family properties in those cities.

The prosecutor found that with the help of Zhai's wife, Li Shuping, who runs a real estate company, two civil servants in the Erqi district's housing administration helped unqualified families buy 27 government-subsidized housing units.