XINING ?-- A man stabbed his wife and two children to death before killing himself, police in northwest China's Qinghai province said Monday.

The man surnamed Cai killed his wife, eight-year-old daughter and seven-year-old son in their home in Wushizhuang Village, Datong County, before committing suicide, said Qi Chunling, head of the county public security bureau.

A police investigation found that the murders happened in the early hours of Sunday morning. Police were alerted at around 12:30 pm.

Cai had been in dispute with his wife, as the couple, both working temporary jobs in nearby cities, did not get along well, according to Qi.