Google says computer hackers in China have broken into the e-mail accounts of hundreds of people, including senior U.S. officials, journalists, and Chinese political activists.

The Internet giant says the scheme to steal user passwords from G-Mail accounts originated in Jinan in eastern China. It gave no details of whose accounts were violated but the White House says it has no reason to believe that any U.S. government accounts were attacked.

Google says the hackers gained the information with a scam called “phishing.” Victims are lured into revealing passwords and other information by responding to fake messages that appear to have come from friends or other trusted sources.

Chinese authorities have not commented.

Chinese-based hackers launched a much wider cyber-attack against Google last year.

Beijing tightly controls Internet material to shield users from what it says is harmful material such as pornography. But human rights groups accuse China of censoring pro-opposition activists.