Around 6:30 pm, eight labourers were coming out of the tunnel in a lift when its cables snapped midway. All of them were killed in the incident, said sub-inspector BN Pawar of Bhigwan police station.
He said most of those killed were from outside Maharashtra, but they are yet to be identified. A police team was at the spot to ascertain their identities.
The river-linking project, launched under the Krishna Bhima stabilisation scheme, involves the construction of the 24.8 km-long Nira-Bhima Link 5 tunnel.
The project, which began in 2012, is designed to take water from water-rich rivers to dry areas.