China said it would relax its lockdown of Wuhan's 11 million residents, only to immediately reintroduce it

• The city at the center of the coronavirus outbreak said it would ease quarantine restrictions on its 11 million citizens, only to reverse the decision just hours later.
• Wuhan announced on Monday that some people who are deemed healthy will be allowed to leave the city, whose transport links have been severed since January 23.
• But authorities later said that announcement was not authorized, and called it "invalid."
• China's decision to lock down Wuhan and nearby cities is the largest quarantine in human history, with the World Health Organization calling it an unprecedented step that's it's not sure will work.
• Visit Business Insider's homepage for more stories.

The Chinese city of Wuhan, the epicenter of the deadly coronavirus outbreak, relaxed the unprecedented quarantine restrictions on its 11 million citizens on Monday, only to almost immediately reverse that decision and reimpose the lockdown of the city.

Wuhan authorities announced an easing of travel restrictions on Monday, which would allow some people to leave the city if they are deemed healthy but said those people would have to be quarantined at their destinations.

But hours later, another statement declared the first announcement "invalid" because it was made without authorization, and said that those who had made the announcement had been "severely criticized."

The city has been under lockdown since January 23, when China cut off transport links to the city and ordered the closure of many public spaces. Footage has showed armed guards patrolling train stations, and the once-bustling city turned into a ghost town.

The second statement said that Wuhan's borders would still be strictly policed.

There were just three hours between the two announcements, Quartz reported. The first announcement no longer appears on the Wuhan government website.

It is not clear if anyone left the city during this time, but it is unlikely given the short time frame between the two announcements and the fact that only certain people were allowed to leave the city.

The lockdown of Wuhan, as well as other cities in the Hubei province, is the largest known quarantine in history.

The World Health Organization has described it as entirely unprecedented, and said it was unsure whether the measure would work to stop the spread of the virus, which has now killed more than 2,500 people in China and infected more than 70,000.

While not all Chinese cities are under the same level of restriction, many have introduced some travel limitations. An analysis done by CNN found that 780 million people - almost half of China's population - were under some kind of travel restriction as of last week.

In Wuhan, people have been shouting support for each other from balconies, making memes and running in their apartments, and minimizing time outside.

The lockdown is part of the Chinese government's efforts to avoid political fallout over the virus, and to make it clear that it is taking action.

But the government is also facing pressure over its response, including calls for freedom of speech protections in the country. On Monday, China's Communist Party also canceled the central event of its political calendar, suggesting it has lost control of the outbreak.

There were more than 40,000 confirmed cases reported in Wuhan as of midnight on Sunday, the city said.

Wuhan's health system is overwhelmed by the virus, and many of those dying are medical professionals who are trying to fight it.

The coronavirus has also spread to at least 29 other countries. Most have only a handful of cases but, as of Monday, it was spreading rapidly in Italy, Iran, and South Korea, where each country is bringing in its own lockdown procedures.

The World Health Organization warned over the weekend that "the window of opportunity is narrowing" to try and contain the virus.

• Read more about the coronavirus:
• Here's what it's like in the isolated city of Wuhan
• Iran, Italy, and South Korea announced harsh new measures to stifle their own outbreaks of the coronavirus
• China canceled the central event of its political calendar because of the coronavirus, a stark symbol of how it has lost control of the outbreak
• The coronavirus may run rampant in some countries least prepared to deal with it. If that happens experts say the virus could become endemic.

• Read all of our coronavirus coverage here.