China on Monday imposed a lockdown in a northern county and travel restrictions in other areas amid a Covid-19 outbreak that has spread to 11 provinces in a week. Ejin, in the Inner Mongolia region, told its more than 35,000 residents to stay at home and warned of civil and criminal action against anyone disobeying the order, state broadcaster CCTV reported. The small county bordering Mongolia is the current outbreak’s hotspot, with nearly one-third of the more than 150 infections found over the past week in the mainland, including half of the 38 new cases announced on Monday. The outbreak of the highly contagious Delta variant of Covid-19 comes as the Chinese capital prepares to host the Beijing Winter Olympics in February. Several housing compounds in Beijing have been locked down, and organisers on Sunday indefinitely postponed a marathon at which 30,000 runners were expected to take part. Another marathon in the central city of Wuhan, where the coronavirus was first identified in late 2019, was also cancelled. Beijing residents have been told to avoid travel out of the capital, while people entering the city from areas with Covid cases must show a negative test. Health officials said cases are expected to rise as testing is increased to contain the outbreak, which has been linked to a group of domestic tourists that travelled across China. Authorities on Sunday suspended inter-provincial tour groups in five areas where cases have been detected, including Beijing. Some cities, including Gansu's provincial capital Lanzhou, and parts of Inner Mongolia have suspended bus and taxi services and closed tourist sites. While the outbreak is relatively small compared to other other parts of the world, China has pursued a zero-case strategy against the pandemic through strict containment measures.