Tunnelling projects across the world are growing rapidly, particularly in India growing at significant rate with 75 projects worth Rs. 49,000 Cr under construction and major new tunnelling projects worth Rs 1.1 lac Cr to be started soon. This makes essential to address the accidents and other incidents occurring in tunnels. In this paper, analysis of multiple case studies is taken into account to find out the causes of tunnel accidents, and its after-effects especially on the long-term stability of the tunnels after counter measures are taken to restabilize such tunnels. The focus of paper is to identify the contributing factors and suggest preventive/safety measures to control and respond to these incidents. Many accidents have been recorded in tunnels in the recent past. For instance, recently, a section of Silkyara-Barkot tunnel located in state of Uttarakhand, India collapsed trapping of 41 workers. Analysis of various tunnel accident-cases reveals that maximum accidents are attributed to negligence, may be in terms of insufficient geological investigation along the tunnel alignment, faulty deformation monitoring and late action for countermeasures etc. By understanding these causes and addressal can help in reducing the risk of accidents and improve long-term stability and safety of the tunnels. The primary aim of this study is to learn lessons from the fatal accidents and suggest some guidelines/measures to be taken in order to minimize/avoid such tunnel accidents in future.