Updated

Chinese state media say police have detained teenage twin brothers suspected of hacking to death six members of a family in northeastern China.

The official Xinhua News Agency said Tuesday that the victims' bodies were discovered Saturday in a village in Heilongjiang province's Qiqihar city.

It says police arrested the brothers, who are under 18 years old. The report does not identify the suspects or the victims and it was unclear whether the twins were related to the victims.

Xinhha says the victims came from three generations of the family and the youngest was 6 years old. The motive for the killings is unclear.

China has seen a string of random attacks that have prompted calls for more attention to mental illnesses and concern over rising stress in Chinese society.