Los Angeles, Jan 13 (IANS) Google has threatened to close its operations and offices in China after hacking of email accounts of many human rights activists.

In a statement on its blog Tuesday, the world's second biggest corporate said it has detected in December "a highly sophisticated and targeted attack on our corporate infrastructure originating from China that resulted in the theft of intellectual property from Google.''

The main goal of the attackers was access the Gmail accounts of Chinese human rights activists, the statement said. But they didn't succeed as "only two Gmail accounts appear to have been accessed, and that activity was limited to account information (such as the date the account was created) and subject line, rather than the content of emails themselves,'' Google said.

But independent of this attack, Google said it has "discovered that the accounts of dozens of US, China and Europe based Gmail users who are advocates of human rights in China appear to have been routinely accessed by third parties.

"These accounts have not been accessed through any security breach at Google, but most likely via phishing scams or malware placed on the users' computers.''

The Mountain View-based company said it has made "infrastructure and architectural improvements that enhance security for Google'' and urged users to deploy anti-virus and anti-spy ware programmes. These attacks, Google said, have forced it to "review the feasibility of our business operations in China.''

The company, which had agreed to censor of Google.cn at its launch in 2006, said it was "no longer willing to continue censoring our results on Google.cn.''

Google said it will soon hold discussions the Chinese soon whether it can operate an unfiltered search engine. "We recognize that this may well mean having to shut down Google.cn, and potentially our offices in China,'' the blog warned.