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SOFIA, Oct 13 (Reuters) - Bulgaria's anti-monopolycommission has "convincing evidence" that six oil companiesoperating in the Balkan country's retail fuel market wereinvolved in cartel agreements on fuel prices, the watchdog'schief said on Thursday.
On Monday the commission accused the Bulgarian units ofLukoil, Royal Dutch Shell, OMV,Hellenic Petroleum, Gazprom Neft andBulgarian Petrol, saying they had collaborated to fixretail prices of diesel and gasoline.
"We have convincing evidence (of a cartel agreement)," saidJulia Nenkova, the commission's chairwoman.
Nenkova said she would not disclose details because ofcommercial and business confidentiality, adding: "I do not thinkthe companies will be able to prove their innocence."
The Bulgarian Petrol and Gas Association, which representsall the companies being investigated, has said there are nocartel agreements between any of its members and it will appealon their behalf.
The six companies have 30 days from Oct. 10 to comment onthe commission's findings. They could face fines of up to 10percent of their annual turnover if found guilty.
The commission began investigating fuel retailers inFebruary after many Bulgarians complained of high fuel costsdespite a plunge in global oil prices. The commission raided theoffices of the companies in April.
The initial inquiry included Rompetrol, which isnot on the list of fuel retailers that the commission says arepart of the cartel.
Nenkova also said that the commission has launched analysesof the banking and the pharmaceutical sectors to check if thereare reasons for price-fixing investigations.
(Reporting by Angel Krasimirov; Editing by Susan Fenton andDavid Goodman)