The labourers were working in an irrigation tunnel constructed as part of the Kaleshwaram lift irrigation project in adjoining Rajanna Sircilla district, Superintendent of Police (SP) Kampati Vishwajith said.
At around 12:30 pm, the roof of the tunnel collapsed, trapping the labourers, the police officer said.
Later, the bodies of six of them were taken out from the debris.
The deceased and the injured are yet to be identified, the SP added.
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