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." "Had Jagroop Singh, the suspected bomber, not botched up the while planting the improvised explosive device (IED), it would have been nearly impossible to crack the case," Dwivedi said, who visited the blast site in the morning. She said the investigation got a critical lead only because the accused died. Dwivedi said that the investigators were still clueless about a similar blast that took place near Sirhind railway station on January 23 this year. The explosion near Sirhind in Fatehgarh Sahib district had left a railway staffer injured, while also damaging a freight engine and railway tracks. Central and state agencies are now investigating potential links between these two incidents to determine if a coordinated campaign is targeting the region's freight network. "We have tried our best to solve the Sirhind blast case, but we have not found any clues so far. Absence of CCTV footage has severely hampered both investigations," she said, adding that video surveillance at regular intervals on the DFC could enhance monitoring to prevent such incidents in the future....