The tougher measures, to take effect Wednesday, include drastically limiting the number of people gathering in public back to four, Chief Executive Carrie Lam said in a press conference on Monday. The limit had just been raised to 50 in mid-June. The city also confirmed its eighth coronavirus death.

Among other measures: Hong Kong will require all inbound travelers to pass a virus test before arriving; restaurants will be allowed to offer only takeout from 6 p.m. to 5 a.m.; and the number of patrons at a table at other times is limited to four. Amusement parks, gyms and 10 other types of venues are to close for seven days. Lam said the city will allow civil servants flexibility on working hours, and urged companies to let staff work from home.

People who refuse to wear a mask on public transport face a potential HK$5,000 ($645) fine.

As part of the clampdown, Hong Kong Disneyland will close on July 15. Hotels serving the resort will remain open, Walt Disney Co. said in a statement.

“They have put in place enhanced health and safety measures that reflect the guidance of health and government authorities, such as social-distancing measures and increased cleaning and sanitization,” the company said.

The former British colony reported 41 local coronavirus cases on Monday, another record daily high as the resurgence of infections looks set to grow into the city’s biggest wave yet. That brought the total to 1,522 cases in a city of more than 7 million people.

Of the 41 cases, 21 are related to previous clusters while 20 were of unknown origin, government officials said Monday.

The significant proportion of cases with unknown origins over the past few days suggests that hidden chains of transmission have been circulating in the Asian financial hub for some time as people returned to work and social activities.

Hong Kong is now facing a major setback in its virus containment fight. After reopening for less than two months, schools have been ordered into an “early summer holiday,” while restaurants and bars limit the number of patrons.

“A containment strategy alone may not be able to slow down the spread of infection at this stage,” Chuang Shuk-kwan, an official with the Department of Health, said on Monday. Senior government officials are “very concerned about the situation now.”

Chuang called for citizens to remain vigilant, and observe personal hygiene and social-distancing practices.

Events including Hong Kong’s week-long book fair and the champion awards dinner by the Jockey Club have been canceled, in a sobering reminder that the pandemic is far from over. Without an effective and widely distributed vaccine, cities are likely to continue in a state of limbo in which any easing of social distancing will lead to a spike of infection.