A multi-agency operation is being carried out to rescue 40 workers trapped inside a tunnel in Uttarakhand since yesterday morning. An under-construction tunnel on the Brahmakhal-Yamunotri National Highway in Uttarkashi district partially collapsed at around 5 am yesterday, leaving 40 workers trapped inside. The rescue operations are being conducted by the National Disaster Response Force (NDRF), State Disaster Relief Force (SDRF) and the police.