In a phishing attack, hackers based in China broke into hundreds of Gmail accounts, including those belonging to senior US government officials and military personnel, Internet serach giant Google has said.

"Through the strength of our cloud-based security and abuse detection systems, we recently uncovered a campaign to collect user passwords, likely through phishing," Google said in a posting on Wednesday.

The Internet giant said it has uncovered a "phishing campaign," which "appears to originate from Jinan, China" in which access was gained to Gmail user passwords and emails, Google Security Team's Engineering Director Eric Grosse said in a blog post.

The "bad actors" hacked into personal Gmail accounts of hundreds of users including, senior US government officials, Chinese political activists, officials in several Asian countries (predominantly South Korea), military personnel and journalists, Grosse added.

"The goal of this effort seems to have been to monitor the contents of these users' emails, with the perpetrators apparently using stolen passwords to change peoples' forwarding and delegation settings."

The Washington Post reported that the personal Gmail account of one Cabinet-level official was compromised.

However, Caitlin Hayden, spokeswoman for the National Security Council, said there is no reason to believe that any official US government email accounts were accessed.