Telangana state government has roped in experts from Geological Survey of India and National Geographical Research Institute besides an Australian part of L&T who has vast experience in tunnels, to suggest the way forward regarding the rescue of eight persons who remain trapped for the fourth day in Srisailam Left Bank Canal tunnel after part of it collapsed on Saturday.

Nagarkurnool District Collector B Santhosh on Tuesday said before taking any step forward stability of the tunnel has been taken into consideration even as dewatering is going on.