Hong Kong, Oct 6 : China has banned residents from leaving Xinjiang over a Covid-19 outbreak - just weeks after the far-western region began relaxing restrictions from a stringent extended lockdown, fuelling public frustration among those scarred by food shortages and plunging incomes, local media reported. On Tuesday, the region - home to 22 million people, many belonging to ethnic minorities - reported 38 new asymptomatic Covid cases, CNN reported. It was enough to alarm officials, with Xinjiang's Vice Chairman Liu Sushe vowing to "strengthen the control of cross-regional personnel and insist that people do not leave the region unless it is necessary". Liu added that Xinjiang will strengthen control measures in airports, train stations and checkpoints to prevent the virus from spreading to other parts of the country. All outbound trains, inter-provincial buses and most flights will be suspended until further notice. At the airport in Urumqi, the regional capital, 97 per cent of departing flights and 95 per cent of arriving flights were cancelled on Wednesday, according to data from flight tracking company Variflight. Meanwhile, all flights departing Kashgar, a southern oasis town home to Xinjiang's second-largest airport, were canceled Â? except for two heading to Urumqi, CNN reported. "The current round of Covid-19 outbreak is the fastest spreading, most widespread, most infectious and most difficult to control public health emergency in the history of Xinjiang," Liu said. Since July 30, Xinjiang has reported a total of 5,790 infections. Liu said that Xinjiang would make sure to "create a favourable environment" for the success of the 20th Party Congress - a meeting of the party elite later this month, where Xi Jinping is expected to be appointed to a third term in power, further cementing his status as the most powerful Chinese leader in decades. The run-up to the congress, the most significant event on the Chinese political calendar, is particularly sensitive, with authorities nationwide working to smooth the way and contain any potential hiccups - like an untimely Covid outbreak, CNN reported. But in Xinjiang, the news of the region's shuttered borders dismayed many residents for whom the pain of the last lockdown is still fresh. /IANS