A city in eastern China has been identified as the world capital of cyber-espionage by an American Internet security company.

The firm traced 12 billion e-mails in a study which showed that a higher number of “targeted attacks” on computers come from China than previously thought.

Researchers for Symantec found almost 30% of “malicious” e-mails were sent from China and that 21.3% came from the city of Shaoxing alone. They were able to identify key targets for the hackers as experts in Asian defense policy and human rights activists, strongly suggesting state involvement.

Symantec is assisting the investigation into suspected hacking attacks on Google, which closed its Web site in China last week rather than censor itself on behalf of the ministry of state security.

Cyber-espionage uses e-mails sent in small volumes with legitimate-looking attachments or documents to fool the user into letting a malicious code infect their computer. “The ultimate aim ... is to gain access to sensitive data or internal systems by targeting specific individuals or companies,” the report said.

Read more at the Times of London.