SEOUL: South Korean prosecutors said they indicted the country's four oil refiners on charges of fuel price collusion, estimated to have caused anti-competitive harm worth US$17 billion, Yonhap News Agency reported on Monday (Jul 6), citing the prosecution.The companies are HD Hyundai Oilbank, SK Energy, GS Caltex and S-Oil, Yonhap said.A spokesperson for the Seoul Central District Prosecutors' Office did not respond to Reuters' phone call and text message seeking confirmation of the report.Prosecutors alleged that pricing managers at HD Hyundai Oilbank and SK Energy colluded on prices for their petroleum products shortly after the outbreak of the conflict in Iran earlier this year, Yonhap said. They discussed the scale and timing of price increases, Yonhap said. GS Caltex and S-Oil also f