A fire has broken out at the onshore Kalamkas oilfield in Kazakhstan's western Mangistau province, the country's emergencies committee said on Monday.
MangistauMunaiGas (MMG), the company which operates the field and is owned by Kazakh state energy firm KazMunayGaz and China's CNPC, could not be reached for comment.
KazMunayGaz said it would comment on the incident and its impact on oil output on Tuesday.
Videos posted by area locals online showed raging fire - which broke out at one of Kalamkas wells before dawn - rising about 10 metres from the ground.
MMG produced 6.4 million tonnes of oil last year - about 7 percent of Kazakhstan's total output - and Kalamkas, its biggest field, has traditionally accounted for more than 60 percent of the company's production.
The company mostly ships oil for exports through pipelines to Russian seaports, but also sends small amounts by another pipeline to China.
(Reporting by Olzhas Auyezov; editing by Simon Cameron-Moore and Louise Heavens)
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