SHENZHEN, China—Direct flights from the southern city of Shenzhen to Beijing have been suspended until at least July 1, booking apps showed, ahead of celebrations for the Chinese Communist Party’s founding in the capital on that date. China’s most populous province Guangdong is battling a COVID-19 outbreak, with 170 confirmed local cases between May 21 and June 21. No new confirmed local cases were reported for June 22. Of the cases, eight were recorded in Shenzhen, while 146 were reported in the provincial capital Guangzhou, though direct flights were still available to Beijing as of Wednesday, booking apps such as CTrip and Fliggy showed. A Shenzhen government official who declined to be identified and two airline representatives confirmed flights from Shenzhen to the capital had been suspended. Flights to other mainland destinations appeared to be operating as normal. The airport in Foshan city, which borders Guangzhou and has seen 12 …