China's leading Xinhua news agency reported the successful flight of the Shenzhou VII hours before the nation's third-ever manned space mission had even lifted off.

On Thursday morning, Xinhua posted a story on its website saying the Shenzhou capsule had been successfully tracked flying over the Pacific Ocean even though the rocket and its three astronauts had not yet been launched.

"There was a technical problem. We dealt with it after we had found it," a editor at the agency told AFP when asked about the story Friday.

The story, dated September 27, was written from one of the numerous tracking ships that China's space programme dispatches around the world to track space flights.

It described in a vivid, blow-by-blow account how the tracking ship was receiving signals from the space craft.

"Changjiang Number One has acquired the target," a tracker was quoted as saying.

"Pressure in the cabin is normal. Oxygen pressure in the cabin is normal."

Late Thursday evening, the Shenzhou VII was launched from the Jiuquan Satellite Launch Centre in northwestern China on a mission that is to include the nation's first-ever space walk.

On Friday, all systems were operating normally, state press reported.