Two Chinese family planning officials were stabbed to death and four others were injured by a man in Dongxing city here after he was denied a residency certificate for his fourth child.
He stormed into the building of the Dongxing City Family Planing Bureau and started attacking the staff, the Dongxing municipal government said.
Two officials died due to stab wounds and four injured people were rushed to hospital.
State television showed pictures of police surrounding the man who was later detained.
Initial investigations revealed that the bureau staff refused to register his fourth child with a permanent residency, or the "hukou," as he had not paid the "social compensation fee" for the child born outside the country's family planning policy.
The fee or the fine has to be paid as people are not permitted to have more children under China's one child policy.
He has four children, one boy and three girls after he got married in 2006.
He also has a history of mental illness and was certified as disabled in June 2010, state run Xuinhua news agency reported.
The incident, regarded as social revenge attack by marginalised people in China is part of several such incidents in recent days, including a suicidal bomb attack by a handicapped person who was paralysed below the waist in a police assault.
In another incident a man went on a stabbing spree in French retail store Carrefour in which one woman was killed and three others including two children were injured.
He too was nabbed and was being interrogated.
Earlier another person stated to be mentally unstable hacked to death an American woman and a Chinese at a commercial complex here.
Officials say these are copy attacks by desperate men to draw public attention to their problems.
