Sixteen days and over 380 hours into their ordeal, the 41 workers trapped under the collapsed tunnel in Uttarakhand's Uttarkashi may face an extended wait, possibly extending for several days or even weeks, before their safe rescue. After repeated setbacks, vertical drilling operations commenced from atop the hill above the collapsed section of the tunnel yesterday. By the end of the day, rescuers had successfully penetrated nearly 20 metres into the mountainside.