China is being hit by a rebound in COVID-19 cases following the weeklong National Day holiday, just as the country’s top leaders gather in Beijing for a meeting with President Xi Jinping.

The nation recorded 1,645 new COVID-19 infections on Saturday, the highest total since Sept. 2. While Inner Mongolia and Xinjiang had the biggest clusters, both Beijing and Shanghai found new cases outside of quarantine, suggesting the virus might be still spreading.

While the eight new cases reported in the capital on Saturday is relatively few, any rebound in infections would pose a headache for leaders. Some 3,000 delegates are gathering in the city to attend the twice-a-decade congress starting Oct. 16 that’s expected to hand Xi a norm-breaking third term in power. A preparatory meeting of roughly 370 members and alternate members of the Central Committee was scheduled to begin Sunday.