By Veronika Gulyas

BUDAPEST--A court in Zagreb on Friday issued a detention order for the chief executive and chairman of Hungarian oil and gas company MOL Nyrt. (MOL.BU), Zsolt Hernadi, after he didn't attend a hearing in a corruption investigation, the court's spokesman told The Wall Street Journal.

Croatia's anti-corruption and organized crime bureau, Uskok, had wanted to question Mr. Hernadi following the 10-year sentence handed down to former Croatian Prime Minister Ivo Sanader in November for corruption. The charges against Mr. Sanader included allegedly taking bribes from MOL for granting the company full management rights over Croatian energy firm INA d.d. (INA.ZG) in 2008. Mr. Sanader, who denied any wrongdoing during his trial, was in office between 2003 and 2009.

"The Hungarian authorities failed to cooperate [with the investigation], saying MOL is in their national interest and therefore it is a question of state security," Kresimir Devcic, the Zagreb court spokesman said. The Hungarian state holds a 24.6% stake in MOL.

The Croatian State attorney's office declined to answer any enquiries on whether Croatia is starting a process to extradite Mr. Hernadi, who is in Hungary.

On Sept. 16 this year, Hungary's Prosecutor General had rejected Uskok's summons for Mr. Hernadi to attend the hearing.

Uskok had suspended its investigation of Mr. Hernadi in December because he was out of reach of the Croatian judiciary at that time. But it resumed the investigation on July 10, after Croatia's accession to the European Union on July 1 provided the conditions necessary to request Mr. Hernadi to attend a court hearing.

If Mr. Hernadi fails to travel to Croatia to answer questions, the country, as an EU member, can issue a European Arrest Warrant, Mr. Devcic said.

MOL's general counsel Pal Kara said he has no knowledge of any request from any Croatian authority for the chairman of MOL to be questioned about the case involving Mr. Sanader.

"The Croatian Court appears to be justifying the issuing of a detention order by an alleged danger of escape, a claim which is both unreasonable and baseless," Mr. Kara said in an e-mailed statement. "I regard the whole case as flawed in form and substance and it appears to be influenced by interests seeking to intimidate both the company and its chairman."

MOL owns a 49.1% stake in INA and holds management rights, while the Croatian government owns 44.8%.

Write to Veronika Gulyas at veronika.gulyas@dowjones.com

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