Four people died and four others were injured after part of a tunnel under construction collapsed Sunday morning in southeast China's Fujian province, local authorities said. The accident happened at around 2:00 a.m. in the Xiazhang (Xiamen-Zhangzhou) Highway Tunnel in the coastal city of Xiamen, the city's publicity department said Sunday afternoon. A total of eight workers were in the tunnel when the accident occurred. Serious injuries left two workers dead en route to hospital, and another two were confirmed dead when rescuers found their bodies at around 7:10 a.m., Xinhua reported. The other four injured workers have been sent to hospital for treatment. The cause of the accident is under investigation.