A 25-year-old man was suspected of attacking a kindergarten in China's Guangdong province on Monday, killing six people and injuring one, police said.
Media reported the attack in Lianjiang county was a stabbing.
The suspect, with the surname Wu and from Lianjiang, had been detained, police said, adding they were investigating.
No other details were immediately available.
Some media reported that both adults and children were among the victims.
While violent crime is rare in China due to strict gun laws and tight security but there have been several incidents of stabbings at pre-schools over the past few years.