Local officials visit an injured tourist at the People's Hospital in Yunyang County, southwest China's Chongqing municipality on July 11, 2009. [Xinhua]

Seven tourists were killed and 12 others remained missing after a rainstorm triggered floods in a canyon in southwest China's Chongqing municipality on Saturday, the local government said on Sunday.

A 35-member tourist group entered an undeveloped mountainous area of the Tanzhangxia Canyon scenic spot in Wanzhou District Saturday afternoon under the guidance of a local resident, according to the government of Wanzhou District.

However, a downpour quickly triggered mountain torrents and flushed away most of the tourists at about 4:00 PM.

The expedition was set up via a Chongqing-based travel website and they did not notify the administration of the scenic spot about their journey or get approval of the local tourism authorities, said Pu Binbin, secretary-general of the Wanzhou District Committee of the Communist Party of China.

More than 400 rescuers retrieved the bodies of seven people and rescued 16 others as of Sunday morning after more than ten hours of efforts.

The injured are in stable conditions in a hospital.

The rescue headquarters are identifying the victims.

More rescuers are joining the search for the 12 missing tourists.