Passengers line up to check in at Liuji Airport in Xiangyang City, central China's Hubei Province, March 29, 2020. Domestic passenger flights resumed operations in Hubei Province except in the Wuhan Tianhe International Airport. (Xinhua/Xie Jianfei)

A total of 412 - about 79.54 percent - of flights in and out Dalian, Northeast China's Liaoning Province have been cancelled as of 9:30 am on Monday, data from Flight Master showed.

The city on Thursday announced it was entering "wartime mode" to battle its new outbreak of COVID-19 linked to a local seafood processing firm. Local authorities have asked residents not to leave the city, and said that those who intend to leave must undergo nucleic acid testing within seven days of their planned departure and present negative results, the Dalian health commission said on Friday.

The city reported 14 symptomatic and 12 asymptotic COVID-19 cases on Sunday, after a 58-year-old man working at a seafood processing company tested positive on Wednesday, breaking the city's record of no COVID-19 cases for 111 days.

Cases related to the new outbreak were largely linked to the Dalian Kaiyang Seafood Company. The 58-year-old man was engaged in the processing and cold storage of imported and domestic aquatic products in the company.

Neighboring provinces including Heilongjiang, Jilin and Southeast China's Fujian have also reported infected individuals who were in close contact with confirmed cases in Dalian.