Two teenagers have been arrested on suspicion of murdering seven people in southern China.
Xinhua said police later learned that the teenagers also killed a couple in Hunan province and a couple in Guangdong province in August.
The two suspects are from Hunan.
Xinhua said money was the likely motive in the slayings, but did not provide further details.
Violent crime rates are believed to be low in China, although government data are usually outdated or incomplete.