(Reuters) - An Iranian oil rig fire may take six months to put out, an official in charge of extinguishing the blaze was quoted as saying on Monday.
Three oil workers were killed and at least 10 injured when the fire broke out on Saturday at well number 24 at the Naft Shahr oil field in Kermanshah province which borders Iraq.
Oil officials declined to specify the output of the Iranian state-owned rig or of the field which Iran shares with Iraq. Naft Shahr, the only active oil field in Kermanshah, has estimated reserves of 692 million barrels, Mehr news agency said.
Kermanshah is hundreds of kilometres north of Iran's main oil producing province of Khuzestan.
"The conditions and the situation of well number 24 in Naft Shahr are different from other gushing oil wells," Heidar Bahmani, head of the National Iranian Drilling Co. was quoted as saying in Monday's edition of Iran daily newspaper.
"The drilling rig and other equipment installed on the wellhead have fused and the volume of the oil bursting from the well is currently unknown," he said.
"Based on international standards in the world oil industry, the minimum time for harnessing and controlling the outburst from such a well is six months," he said. Previously officials had said it would take up to a month to control the fire.
OPEC member Iran is the world's fourth biggest crude exporter.
(Reporting by Hashem Kalantari; writing by Robin Pomeroy; Editing by Keiron Henderson