Local media report that the case was centred on officials with ties to Bosnia's textile mafia

* Bosnia's biggest-ever operation against graft, financial crime

* Total of 54 people detained

* Accused of dodging taxes, customs fees on textiles and cars (Adds figures, quotes)

SARAJEVO, June 18 (Reuters) - Dozens of customs and tax officials have been detained in Bosnia, accused of defrauding the state of more than $1 billion in customs revenue on imported textiles and cars, authorities said on Wednesday.

Codenamed "Pandora", the operation was believed to be the biggest against graft and financial crime in Bosnia's more than two decades as an independent state.

A total of 54 people were rounded up in raids on dozens of locations across the Balkan country, where a decentralised system of power-sharing since a 1992-95 war has helped foster networks of political patronage and corruption.

Among those detained were 30 customs and tax officials, including the former head of the indirect taxation authority (ITA), the prosecutor's office said in a statement.

"Through the customs fraud alone, a loss of over 2 billion Bosnian marka ($1.4 billion) was inflicted on Bosnia's budget from 2006 to 2010," ITA Director Miro Dzakula told a news conference in the northwestern town of Banja Luka. His own assistant was among those detained.

The figure is equivalent to almost 10 percent of national economic output in the impoverished Balkan country, still recovering from a 1992-95 war. In 2010 alone, Dzakula said, Bosnia lost out on 350 million marka in customs fees on imported Chinese textiles.

The investigation is the latest to target corrupt officials in recent years, though critics say that in the past only a small number of those initially detained have ended up behind bars.

Mehmedalija Osmic, the president of ITA trade union, said the operation was a "victory" for Bosnia and the ITA workers, and hinted at political connections.

"It was a chain of theft starting from customs officials and their superiors through to the ITA director and the political structures," he said. (Reporting by Daria Sito-Sucic; Editing by Larry King)

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