Why have Nirbhaya’s killers been put on suicide watch?

Bengaluru: The four convicts in the Nirbhaya case; Mukesh Singh, Pawan Kumar Gupta, Akshay Thakur and Vinay Sharma were moved to Jail Number 3 on January 16. All the four are under close observation and have been kept on suicide watch. We find out how authorities at Tihar are keeping a watch on the four killers and the reasons behind the measures taken as Simplified By Pratiba Raman.