JINAN, Aug. 20 (Xinhua) -- A man in east China`s Shandong Province have been arrested after allegedly killing four, including his wife and son, and injuring two, local authorities said Saturday.

The killing spree occurred at about 3 a.m. Friday in Da`an township in the city of Yanzhou, the Yanzhou city publicity department said in a statement, without giving the reason of the tragedy.

The suspected killer Gu Zhen was arrested at the scene, it said.

A police investigation showed Gu killed his wife and two neighbors at the scene, while his son died at hospital after emergency medical treatment failed.

The two injured are being treated at hospital.

Local police are further investigating the case.