Patiala, April 29 -- Lack of video surveillance along the dedicated freight corridor (DFC) would have made it impossible to crack the Monday night blast case had the accused not died, giving investigators vital clues, special director general of police (railways) Shashi Prabha Dwivedi said on Tuesday.

The blast occurred around 10pm near Bathonia village on the Rajpura-Shambhu railway line in Patiala district on Monday night, an incident senior police officials said was a botched "attempted detonation."

Suspected bomber, Jagroop Singh of Panjwar Khurd in Tarn Taran district, was killed when his explosive device detonated prematurely.

"Had Jagroop Singh, the suspected bomber, not botched up the while planting the improvised explosive dev...