The two suspects were described by the Prosecutor's Office as the head of the maintenance department of the power plants of VKG Energia OÜ and the head of the operations department of VKG Soojus AS.

Sergei, 52, and Vjatšeslav, 48, are suspected of accepting bribes on repeated occasions, making use of their official positions in return for ensuring that tenders were won by specific businesses. The bribes were given in the form of cash and services.

A board member of one of one business has been declared a suspect in bribe-giving and a board member of another business in counterfeiting a document.

Searches have been conducted on the premises of VKG and the businesses involved. Both VKG employees declared suspects in the investigation as well as the board member of one business were detained but released after initial investigation procedures were conducted.

VKG, a privately held oil shale mining and shale oil production company, has terminated the employment contracts with both employees.

Mati Ombler, head of the Office for Combating Corruption Crimes at the Central Criminal Police, said that police are paying increasing attention to detecting corruption in the private sector.

"By identifying corrupt employees in the private sector, we prevent the spread of corrupt practices and the conclusion of harmful contracts as well as ensure fair competition," he said. "We recognize the effective work of internal audit at VKG and the management's zero tolerance for corruption."

VKG CEO Ahti Asmann ssaid that the company's management considers corruption impermissible and is convinced that observance of the principles of fair competition is the basis of every business activity.

"While the degree of guilt of the persons declared suspect will be determined by the courts, for us this is sufficient grounds for losing trust and canceling employment contracts with them," Asmann said. "We have zero tolerance for this kind of unlawlful activity."