MOSCOW: Kazakhstan's daily oil and gas condensate production fell 6% in early January from December levels, according to two industry sources and Reuters calculations, as mass anti-government protests rocked the country.

Output from Kazakh oil fields fell to 1.766 million barrels per day (bpd) in the first nine days of the month from an average 1.882 million bpd in December, calculations showed and the sources said, citing preliminary daily output data.

The protests in Kazakhstan, which saw the deadliest violence in the country's 30 years of independence from Moscow, disrupted transport routes and led to production curbs at oil fields including the giant Tengiz field operated by Chevron .

Chevron said on Sunday that the company had been gradually increasing output at the field, which is located in the north-west region of Kazakhstan close to where the protests started, after a temporary decline.

According to the data, daily oil output at Tengiz was down 13% from its December average in the first nine days of the month, the sources said and Reuters calculations showed. As of Jan. 9, it was back to normal, the sources added.

Other fields located further from protests managed to increase output.

Production at the offshore Kashagan oil field operated by North Caspian Operating Company (NCOC) was 0.2% higher during the period than in December, while at the Karachaganak oil field in western Kazakhstan it was up by 6%, according to the sources.

Output at smaller independent Kazakh oil producers has fallen by 17% so far in January to 210,918 bpd compared to the previous month.