People in China are able to access English language stories on the BBC News website in full, after years of strict control by Beijing.
The Communist authorities often block news sites such as the BBC in a policy dubbed the "great firewall of China".
But BBC staff working in China now say they are able to access news stories that would have been blocked before.
However, the firewall remains in place for Chinese language services on the website and for any links in Chinese.
Beijing has never admitted to blocking access to BBC news stories - and there has been no official confirmation that the website has been unblocked.
But Chinese users trying to access pages on the site have almost always been redirected to an error message telling them: "The connection was reset."
It now appears that this is no longer the case, and access to the site is much easier.
Steve Herrmann, editor of the BBC News website, says this is a welcome development.
"We want BBC News to be as accessible in China as anywhere else in the world," he said.
"We will endeavour to continue working with the Chinese authorities to improve our access in other areas."
Technology experts say such a development would not be possible without the approval of internet service providers - which are under strict supervision by Beijing.
Statistics show that traffic to the website from China has been much higher than usual.
Typically fewer than 100 people read stories from Chinese computers - but on Tuesday that figure jumped to more than 16,000.
And comments have been flooding in to BBC forums from all over China.
Ross Brown in Qingdao, Shandong province, wrote: "We were just discussing with some of our Chinese colleagues about the fact BBC website was blocked, went on to show them and we see this latest news. Excellent news."
Many of the comments came from readers of the website who have spent years accessing the stories by linking their computers to others based outside of China.
The Chinese authorities had promised to give foreign journalists more freedom in the run-up to this summer's Olympic Games.
But analysts say that recent outbreaks of unrest in Tibet have made this promise more difficult for Beijing to uphold.
The BBC and other media organisations still find reporting from Tibet very difficult - foreign journalists were refused permission to enter the region during the recent protests.
The websites of UK newspapers the Times and Guardian - as well as video-sharing site YouTube - were blocked or partially blocked during the unrest.
This week the Chinese government has arranged a trip for foreign media organisations to Tibet - but the BBC's request to be included was rejected.
Although no official ban has ever been announced, the BBC News website has been blocked for almost a decade.
The Chinese language website has been blocked since its launch in 1999.