She also dismissed claims that she had threatened a former member of the management board of the state-owned insurance company Croatia Osiguranje and USKOK's witness in the Fimi-Media case, Damir Mihanovic.

"I am proud of everything I did as Prime Minister and HDZ president to improve the political climate supporting the fight against corruption and crime, and my political engagement was based on the message that thieves must end up behind bars," Kosor said at a news conference.

She added, however, that she had been aware that the anti-corruption drive would "at some point" boomerang against her and her party. She noted that she considered the current pressures against her as part of intra-party campaigning for a new HDZ leader.

Commenting on media reports alleging that money from the party's slush funds had been kept in the party's safe until October last year, Kosor said that she had told everything she knew about the safe at the Office of the Chief State Prosecutor, as had the party's secretary-general, Branko Bacic.

"I meant every word I said then," Kosor said, adding that it was interesting that Damir Mihanovic, former member of the Croatia Osiguranje management and USKOK's witness in the Fimi-Media case, was reappearing again in the case as a key witness.

In the latest political talk show "Nedjeljom u dva" on Croatian Television on Sunday, Mihanovic accused Kosor of having known that the money the then customs chief Mladen Barisic in January 2010 gave to HDZ accountant Marica Glavas had come from slush funds and that despite that, the money was kept in the party's safe until October 2010. Mihanovic also said that Kosor had threatened him.

Distributing to reporters four e-mails sent to her by Mihanovic in 2009 and 2010, Kosor said she found interesting the names stated in those e-mails and the people Mihanovic was accusing.

The e-mails in question mention, among others, former Croatia Osiguranje director Hrvoje Vojkovic who Mihanovic claims had awarded a private company owned by former Minister of the Interior Tomislav Karamarko a consultancy contract at Croatia Osiguranje. Mihanovic also accuses Vojkovic of having hired to work at Croatia Osiguranje the wife of former police director Oliver Grbic.

Kosor dismissed Mihanovic's claims that she had threatened him, saying that she had never threatened anyone.

Commenting on accusations by some candidates for HDZ president that she was responsible for the recent dissolution of the HDZ branch in the eastern town of Valpovo, Kosor said she had not been informed that the party branch would be dissolved and that she had neither ordered nor requested it.

She added that the decision to dissolve the party branch was an autonomous decision of the HDZ branch in Osijek-Baranja County, noting that its timing was not the most opportune one.

"It proves how the party operates under the new leadership," she said, adding that the party leadership was not issuing orders that something be done or that something not be done.

"I dismiss insinuations from HDZ presidential candidates who are attacking me with all their might. They have missed the target, but that is all part of a big campaign in which the stakes are obviously very high," Kosor said, adding that she considered it an attempt to eliminate her from the race for party president.

Asked who could be behind media attacks against her, Kosor said she did not want to elaborate, but added that she had evidence and would see what to do with it.