Five residents were killed and nine others were injured in an attack in Yunnan province on Friday morning, according to the local publicity authority.
The murders happened at about 7 am in Gazhong village when the 21-year-old suspect started slashing his grandfather and his mother with a knife, then ran out of the home and attacked and killed others, said Lin Yineng, a publicity official in Dehong.
The grandfather's and mother's injuries were not life threatening, but they were hospitalized.
Victims included a tractor driver, a resident surnamed Wang told Beijing News.
The suspect, a local resident, was caught by police.
An initial investigation reveals that the suspect might have a mental disorder, according to Lin, but the motive is still under investigation.
Lin said the suspect had been working in Yancheng, Jiangsu province, and went home about a month ago. Police officers have been dispatched to Yancheng for investigation, he said.
Another resident, surnamed Yu, told the newspaper that the suspect went back home and took a shower after the murders and appeared very calm.
Liu Wenwen contributed to this story.