The preventive arrest measure may be appealed.
Iordache allegedly embezzled money that was supposed to go into the construction of the Nadlac-Arad highway, which his company Romstrade was building.
Romanian authorities have recently terminated the contract for the construction of a section of the Nadlac-Arad highway, which was being built by a consortium that included Romstrade, citing delays in works.
In 2011, Romstrade posted a profit of EUR2.6 million, down to a half of its 2010 profit, according to Forbes Romania.
In 2009, Romstrade was the biggest local construction company, with profits of more than EUR31 million and a turnover of EUR268 million.
Iordache was ranked 28th in the 2011 edition of the Forbes 500 Billionaires with an estimated wealth of EUR150 million.