Four labourers were killed and six injured while many trapped in the debris when a bridge under construction over Chambal river collapsed near a bypass in Rajasthan's Kota district on Thursday, police said.

Kota Collector T Ravikant said relief operations have already begun and Army's help has been sought as the number of labourers trapped is still not known.

The reason behind the collapse of the 50-metre bridge, being constructed by a Korean company, is being ascertained.

Keywords: bridgecollapseKotaRajasthan