Source: South China Morning PostChina has tightened security along the southwest border with Vietnam as its neighbour grapples with its worst outbreak of Covid-19 and a new variant that appears to spread quickly.The 1,297km (806 mile) border has been closed to foreign visitors on both sides since the pandemic began, but China began allowing in those with permits in September, while officials, foreign investors and skilled workers are exempted and can enter Vietnam.Now, as Vietnam tries to contain a rising number of infections…Read More