China has closed off its borders to foreigners as the virus spreads globally, though most imported cases have involved Chinese nationals returning from overseas.
Of the new cases showing symptoms, 38 were people who had entered China from abroad, compared with 25 a day earlier.
Of those, 20 had arrived in the northeastern province of Heilongjiang from neighbouring Russia, the provincial government said. All were Chinese citizens who had flown from Moscow to Vladivostok, including 12 who were on the same April 2 flight, and travelled to China by road.
Another possible source of infection is the roughly 1.6 million Chinese citizens who study overseas, many of whom have struggled to return home since Beijing cut international flights into the country.
Preparations are under way to arrange charter flights to bring home Chinese students studying in the United States, starting with the youngest, China's embassy to the United States said.
One new locally transmitted infection was reported in the latest data, in the southern province of Guangdong, down from five a day earlier in the same province.
The new locally transmitted case, in the city of Shenzhen, was a person who had travelled from Hubei province, Guangdong provincial authorities said.
The Guangdong health commission raised the risk level for a total of four districts in the cities of Guangzhou, Shenzhen and Jieyang from low to medium late on Sunday.
