Some of China’s most persistent virus hotspots have been locked down for weeks, and in some cases months, showing the limitations of the country’s contentious COVID Zero policy.

Xinjiang reported the fourth-highest number of new cases nationally for Monday, according to data compiled by Bloomberg, despite some cities in the region in China’s northwest locked down for 90 days. Inner Mongolia, which was sealed off in early October, saw cases jump to almost 1,800 from 1,033 a day earlier, while Henan province’s infections more than doubled in a day to 747.

Guangdong province has the biggest outbreak right now, the main driver of China’s national caseload rising to 7,323 new infections, the highest tally since April 30. Most of the cases are in the southern metropolis of Guangzhou, which reported 2,377 infections and has taken a targeted approach to virus containment so far.

While entertainment venues and restaurants are shut in most of the city, just one district, Haizhu, has been locked down. It’s where most of the cases are being found, and the stay-at-home order was extended on Monday night.

Restrictions continue to be imposed at various levels in other Chinese cities, with Shanghai consistently locking down apartment blocks and neighborhoods where cases and close contacts are found since its city-wide lockdown was ended earlier in the year.

The swelling outbreaks show the strain China’s COVID Zero strategy is facing, with even harsh lockdowns and constant mass testing failing to quickly get them under control. Health officials over the weekend reaffirmed the country’s unswerving commitment to the policy, even as it hammers the economy, dashing hopes that authorities will soon move toward easing some of their strictest rules.

China’s absolutist approach to COVID almost three years into the pandemic is leading to rising tensions on the ground.

A clash between residents and virus prevention staff — known locally as Dabai, or “Big Whites” for their full-body PPE — in Shandong province led to seven arrests on Monday, police in the city of Linyi said on Weibo.

A video posted online purporting to be of the fight showed groups of Dabai surrounding a man on the street, then dragging him by his clothes before punching and kicking him on the road, joined by what appears to be police officers. Onlookers scream and yell. Bloomberg News was unable to verify the footage, posted across Weibo and also on Twitter.

China quarantines all COVID cases and their close contacts in makeshift hospitals, a policy that has led to frictions in the past as people object to being taken away.

Incidences of pushback and protest are increasing in China the longer COVID Zero drags on. In the lead-up to the all-important Communist Party congress in Beijing last month, a protester hung banners from a bridge criticizing the lockdowns in a rare, high-profile show of defiance in the capital. Videos of protests during Shanghai’s lockdown earlier this year were censored online.