The government is making sincere efforts to rescue 40 workers trapped inside an under-construction tunnel in Uttarakhand, but a serious rethink is required on how to develop infrastructure in the Himalayan region, an expert has told NDTV. Dr Sudhir Krishna, former secretary of Union Urban Development ministry, said there are multiple challenges in rescuing the workers, who have been trapped for more than 70 hours now. They have been provided food, water and oxygen, but attempts to bring them out have been hampered by landslides. New equipment is now being flown in from Delhi to assist in the rescue work.