In Shenzhen, the country’s southern tech hub, authorities have placed 17.5 million people under stay-at-home orders for the next week, while health authorities race to carry out citywide testing. The city’s lockdown began on Sunday, when authorities reported 66 new COVID cases, bringing Shenzhen’s total to over 400 since late February.

Shenzhen’s rapid, assertive response to a relatively minor caseload stands in stark contrast to the fumbling and ineffective containment strategies adopted by its neighbor, Hong Kong, a Chinese special administrative region that’s a 15-minute train ride away from Shenzhen and now has the highest COVID death rate in the world.

Hong Kong, which maintains a semipermeable border with Shenzhen, is the source of most of Shenzhen’s rising COVID cases, and some citizens in mainland China are blaming their latest lockdown on the incompetence of their southern neighbor.

“Why is Hong Kong experiencing such privilege? No lockdowns, no citywide tests?” one user on China’s Twitter-like Weibo posted as Shenzhen enforced its lockdown. “Why is our taxpayer money going to these bastards? Hong Kong is part of China, but the people are not necessarily our compatriots.”

Hong Kong does not receive taxpayer money from mainland China, but the city has turned to mainland authorities for help as it struggles to contain a fifth wave of COVID infections.

Hong Kong reported 26,908 new COVID cases on Monday, down from a peak of 56,000 two weeks ago, as the city reels under a crushing Omicron outbreak that began in early February.

The local government’s response to the wave of infections has appeared useless in preventing transmission of the highly virulent COVID strain. Hong Kong has banned indoor dining after 6 p.m., closed all bars and gyms, limited restaurant bookings to two per table, and tightened rules for mask-wearing.

The government has also flip-flopped on some bizarre policy ideas, such as a plan to move forward schools’ summer vacation so empty school buildings could be used as quarantine centers. Last week, Hong Kong also decided to reopen hair salons, even as daily case numbers trended above 30,000.

Hong Kong’s leaders also sparked panic buying early this month when the government warned health officials would conduct citywide testing during early March. But after stoking fear and spending millions to build new quarantine facilities to house the positive cases a citywide campaign would turn up, the government has postponed its plan for mass testing without setting a new date.

“If you ask Hong Kong to learn from Shenzhen today and hold a three-round compulsory universal testing campaign within days, I’m afraid we don’t have that level of capacity,” Hong Kong Chief Executive Carrie Lam said Monday.

Lam has also consistently said that Hong Kong won’t implement a mainland China–style lockdown in the city. Now, with cases building in Shenzhen, some mainland China residents are angry that Hong Kong has yet to enact stay-at-home orders and that Hong Kongers continue to socialize outside.

“Shenzhen and Hong Kong are both being threatened by the severe pandemic situation, but I am so angry that Hong Kong citizens are ignoring the risks and could not hold back their excitement to ‘cool themselves down’ at the beach,” one Chinese netizen wrote Sunday.

Despite the government officially banning group gatherings of more than two people, Hong Kong’s beaches were crowded with sunbathers last weekend. On Monday, Shenzhen reported 26 new imported COVID cases, 24 of which came from Hong Kong, continuing a trend of cross-border transmission.

As cases and deaths escalated in Hong Kong last month, thousands of residents fled across the border into mainland China, and some of those escapees brought COVID with them. Shenzhen, which provides 90% of Hong Kong’s fresh produce, has also imported COVID cases through cross-border trade with its southern neighbor.

“Shenzhen residents are blocking imported cases from Hong Kong with their lives. As a result, Shenzhen still has to provide supplies to Hong Kong even after being locked down. Why? Hong Kong is so precious that the country has to serve it?” one mainland China resident said.