A man has confessed to killing 19 people in one village after an argument with his parents over money.
The Xinhua news agency, quoting police, said Yang Qingpei first murdered his mother and father, then went on a killing spree of their neighbors to prevent them reporting his crime.
A list of the victims' names circulating online showed they included 11 males and eight females, with the youngest a three-year-old girl and the oldest 72.
Four names were minors under 18.
The mass killing took place in the village of Yema in China's mountainous Yunnan Province.
Yunnan police said 27-year-old Yang was arrested more than 120 miles away in the provincial capital of Kunming after 33 hours of "arduous investigation".
But video footage circulating online reportedly from Yema itself showed police and heavily armed officers walking the streets and a young man in jeans handcuffed on the ground.