The two are accused of bribery related to an electricity sale contract.
The court ruling placing the two under preventive arrest is not final and may be appealed.
Investigators said Mihaila, in October, promised another member of Hidroelectrica’s supervisory board EUR1.4 million in exchange of his favorable vote on a bilateral energy trading contract that would have had the state company selling energy at a loss. Bradean is accused of accessory to bribery.
The proposed bilateral contract was voted down by the company’s board.