The mistreatment or injustice one suffers never justifies the harm he or she does to other innocent people. This should be the principle by which we judge the violence that has taken place in recent weeks.

In the latest incident, a 41-year-old man hacked three people to death and injured another three in the city of Shenzhen, South China's Guangdong province, on Monday. Last week in Beijing, a 2-year-old girl died in hospital after a man snatched her from her stroller and threw her on the ground during a row with her mother.

In Hailun city, Northeast China's Heilongjiang province, a resident at a nursing home for the elderly set fire to the facility on Friday, killing 11 people, because he suspected someone had stolen his money.