India, June 26 -- A 640-minute period during which murder accused Chetan Chaudhary deliberately remained offline on the day Pune realtor Ketan Agarwal died has emerged as a key breakthrough in the police investigation, with investigators saying the move ultimately helped them trace his alleged role in the murder conspiracy.

Siya Goyal, a 20-year-old woman from Maharashtra's Pune, is accused of killing her fiance Ketan Agarwal, by pushing him off a cliff during a trek to Lohagad Fort near Lonavala on June 18 with the help of Chetan Chaudhary, 22 - allegedly a man who she was in a relationship with.

According to police, Chetan switched off the internet connection on his mobile phone at around 7 am on June 18 and remained offline until 5:4...