Police said here on Tuesday that the soil lifting machine (loco) overturned following its brake failure on Monday night during construction of the tunnel 60 ft below the ground near Patna University.
A labourer was killed on the spot and six others were injured in the mishap.
The injured were rushed to the hospital where one of the labourer succumbed. The other injured were undergoing treatment at the local hospital.
The sources informed that 25 labourers were working inside the tunnel at the time of the accident. Both of the deceased were inhabitants of Odisha.
