A Chinese security official has been arrested on suspicion of spying for the U.S., Reuters reports.

Sources say both counties have made an effort to keep the case quiet for months. The official was detained earlier this year after allegedly passing along information to the U.S. regarding China's espionage activities.

The New York Times said the official, was believed to be an employee in the Ministry of State Security, China's main intelligence agency.

The U.S. and Chinese governments have not given any hint publicly of the discovery of the spying suspect. Secretary of State Hillary Clinton, visiting Oslo on Friday, declined to comment on the reports.

Reuters and AFP contributed to this report.