Pacak's attorney Mate Matic said his client was arrested at 2130 hours Tuesday upon returning from Tunisia where he was staying at the time an investigation was launched against him and Milkovic.

As a warrant has been issued for his arrest in the meantime and a month-long detention set against him due to the risk of his tampering with witness, Pacak was taken to the Remetinec prison immediately from the airport. Later today he will be taken to the anti-corruption agency USKOK for questioning, lawyer Matic said

He added that since the launching of the investigation, Pacak had been claiming he would return to Croatia and present his defence to USKOK.

USKOK opened the investigation into Milkovic on the suspicion that he took bribes at the time when he was a sector director at the Crosco company and later as Crosco's Management Board chairman, in collusion with Pacak, a former platform overhaul project manager at Crosco.

Crosco is an on- and offshore drilling and well services contractor which is part of INA Group.

Milkovic and Pacak are suspected of having solicited bribes, in the period from 2002 to 2009, in exchange for awarding job contracts to other companies. The bribes ranged from 5 to 10 percent of the net contract value.

The persons who were asked to give bribes did so in order to win tenders which they needed so their businesses could continue operating, USKOK said.