After two years of separation from his wife in mainland China, Hong Kong resident Cheung Seng-bun made sure he was among the first to cross the border following the reopening of crossing points Sunday.

The ability of residents of the semi-autonomous southern Chinese city to cross over is one of the most visible signs of China's easing of border restrictions, with travelers arriving from abroad also no longer required to undergo quarantine.

“I'm hurrying to get back to her,” Cheung, lugging a heavy suitcase, told The Associated Press as he prepared to cross at Lok Ma Chau station.

Travelers crossing between Hong Kong and mainland China, however, are still required to show a negative Covid-19 test taken within the last 48 hours — a measure China has protested when imposed by other countries.

Hong Kong has been hard-hit by the virus, and its land and sea border checkpoints with the mainland have been largely closed for almost three years. Despite the risk of new infections, the reopening that will allow tens of thousands of people to cross each day is expected to provide a much-needed boost to Hong Kong's tourism and retail sectors.

China's borders remain largely sealed, however, with only a fraction of the previous number of international flights arriving at major airports. That number is expected now to tick upward, with Beijing's main airport preparing to reopen arrival halls that have been quiet for most of the past three years.

China is now facing a surge in cases and hospitalizations in major cities and is bracing for a further spread into less developed areas with the start of the Lunar New Year travel rush, set to get underway in coming days. While international flights are still reduced, authorities say they expect domestic rail and air journeys will double over the same period last year, bringing overall numbers close to those of the 2019 holiday period before the pandemic hit.

China has said the testing requirements being imposed on its travelers by foreign governments — most recently Germany and Sweden — aren't science-based and has threatened unspecified countermeasures.

Chinese health authorities publish a daily count of new cases, severe cases and deaths, but those numbers include only officially confirmed cases and use a very narrow definition of Covid-19-related deaths.

Authorities say that since the government ended compulsory testing and permitted people with mild symptoms to test themselves and convalesce at home, it can no longer provide a full picture of the state of the latest outbreak.?

Government spokespeople have said the situation is under control and reject accusations from the World Health Organization and others that it is not being transparent about the number of cases and deaths or providing other crucial information on the nature of the current outbreak that could lead to the emergence of new variants.?

Despite such assertions, the Health Commission on Saturday rolled out regulations for strengthened monitoring of viral mutations, including testing of urban wastewater. The lengthy rules called for increased data gathering from hospitals and local government health departments and stepped-up checks on “pneumonia of unknown causes.”?

Criticism has largely focused on heavy-handed enforcement of regulations, including open-ended travel restrictions that saw people confined to their homes for weeks, sometimes sealed inside without adequate food or medical care.?

Anger was also vented over the requirement that anyone who potentially tested positive or had been in contact with such a person be confined for observation in a field hospital, where overcrowding, poor food and hygiene were commonly cited.

The social and economic costs eventually prompted rare street protests in Beijing and other cities, possibly influencing the Communist Party's decision to swiftly ease the strictest measures and reprioritize growth.?

As part of the latest changes, China will also no longer bring criminal charges against people accused of violating border quarantine regulations, according to a notice issued by five government departments on Saturday.?

Individuals currently in custody will be released and seized assets returned, the notice said.?

The Transportation Ministry on Friday called on travelers to reduce trips and gatherings, particularly if they involve elderly people, pregnant women, small children and those with underlying conditions.