The court heard Ante Kotromanovic and two lawyers for fugitive general Ante Gotovina, Ivo Farcic and Marin Ivanovic.
Farcic told Hina he had made a statement before investigating judge Kresimir Devcic, but declined to reveal details of the hearing, saying that it was declared classified.
Kapetanovic is suspected of falsely reporting a criminal offence after he said he met Gotovina, who is wanted by the Hague tribunal on war crimes charges, last year.
Kapetanovic told prosecutors in mid-January that he had met Gotovina in Bosnia-Herzegovina last November in order to persuade him on behalf of the Croatian government to surrender to the Hague tribunal.
A source close to the prosecution told Hina on condition of anonymity that a preliminary investigation had shown that Kapetanovic had not met Gotovina and that he had not been authorised by the Croatian state leadership to negotiate with the fugitive general.
Kapetanovic has claimed that some people assisted him in establishing contact with Gotovina, including retired brigadier Ante Kotromanovic. Prosecutors believe that this is not true.