Two passengers and an airport staff (left) walk in a nearly empty terminal at Beijing Capital International Airport, in Beijing, on April 13, 2020. (NICOLAS ASFOURI / AFP)

China's capital Beijing will strengthen management of travelers from overseas and domestic medium and high-risk areas in order to avert a rebound of local cases, senior officials said on Tuesday.

Lei Haichao, head of the Beijing Municipal Health Commission, said at the COVID-19 epidemic control and prevention conference held on Tuesday afternoon that risks and challenges still exist in the city, and continued vigilance is needed.

The conference came ahead of this year's "two sessions"－China's biggest annual political event－which will begin on May 21

"Beijing is an open city with a high level of internationalization," he said.

"It's also the national political, cultural, international communication and scientific technology innovation center, which leads it to have close connections with other areas domestically and globally. This creates difficulties in epidemic control and prevention."

The conference came ahead of this year's "two sessions"－China's biggest annual political event－which will begin on May 21.

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Thousands of deputies to the National People's Congress, the legislative body, and members of the National Committee of the Chinese People's Political Consultative Conference, the top political advisory body, will gather in Beijing to hold political discussions.

There are currently more than 4 million confirmed COVID-19 cases in the world.

There are also international flights still coming to China every day, which brings certain risks to all Chinese cities regardless of where the flights arrive, according to the commission.

Domestically, new confirmed cases have recently sprouted in Heilongjiang, Jilin, Liaoning and Hubei provinces as well as the Inner Mongolia autonomous region.

This could cause a rebound in cases in the capital if people from those regions travel to the city.

"We should take stricter measures and implement a higher level of prevention to ensure safety in Beijing," Lei said.

Xu Hejian, spokesman for the municipal government and director of its information office, said on Tuesday that Beijing will continue prevention measures such as temperature-taking and inspecting people's health codes in communities.

According to the authority, as of Monday Beijing still had 13 confirmed cases in the hospital, 10 of whom are imported cases.

On Monday afternoon, Beijing's anti-virus leading work group held a meeting, hosted by Beijing's Party chief Cai Qi, to discuss the city's epidemic control and prevention efforts.

According to the meeting, authorities should guide people to continue wearing masks.

In addition, schools where the students have resumed classes should strengthen control and prevention efforts and prepare detailed emergency plans.

READ MORE: Beijing taking steps to bolster control efforts

Meanwhile, the municipal government will also focus efforts on protecting city-owned enterprises' overseas staff and projects.