BEIJING - China detected 91 domestically transmitted COVID-19 cases with confirmed symptoms for Tuesday, marking the highest daily count since Nov. 2 and a significant jump from 21 cases a day earlier, as the country fights a fresh outbreak in the north.

All of the 91 local symptomatic cases were reported in the northern Chinese region of Inner Mongolia, data from the National Health Commission showed on Wednesday.

Mainland China has not detected any infections caused by the Omicron variant, Xu Wenbo, an official at Chinese Center for Disease Control and Prevention, said on Tuesday at a news briefing.

Inner Mongolia reported a total of 132 local symptomatic cases during the Nov.28-30 period, more than 70% of them in Manzhouli, a small city next to the border with Russia.

Although the number is low compared with many outbreaks outside China, Manzhouli has quickly banned residents from leaving town, halted some non-containerised imports by rail and closed a flurry of public venues, as Beijing sticks with its zero tolerance approach towards letting infections spread.

The latest resurgence in cases comes only a few weeks after Inner Mongolia contained a cluster that was part of China's biggest Delta outbreak between mid-October and mid-November.

The early local infections in Manzhouli were found in routine screening test among workers who handled imported goods, a health official in Inner Mongolia told state television late on Tuesday, adding that authorities are confident to contain the flare-up within 14 days.

As of Nov. 30, mainland China had confirmed 98,824 symptomatic cases, including both local ones and those arriving from abroad. The death toll remained unchanged at 4,636.

(Reporting by Roxanne Liu and Gabriel Crossley; Editing by Christopher Cushing and Lincoln Feast.) ((Gabriel.Crossley@thomsonreuters.com; +86 10 5669 2127;))