Ghaziabad, May 30 -- The Ghaziabad police investigating the murder of Noida police constable Saurabh Kumar during a raid at Nahal village on May 25 night, has hit a roadblock with no CCTV footage emerging about the scene of crime where the cop is believed to have been shot, investigators said. Sleuths said the constable fell off a motorcycle moments before the incident. "Saurabh was driving a bike. Moments later, the bike hit a speed breaker on the road, and this was the moment when Saurabh sustained a gunshot. The bike fell, as did Saurabh and other constables. He fell several feet away after the speed breaker," said an officer attached to the case investigation. Police have maintained that the autopsy report has suggested that Saurabh was shot from "close range" with a "firearm" injury, and the bullet made an entry and an exit in his head. The Noida police, in their FIR, have said they were twice attacked and fired upon indiscriminately by the mob acting against the arrest of local Qadir. But Ghaziabad police investigating the case said there was no evidence of indiscriminate fire, and only a single bullet casing was found at the scene of the crime. The officers, however, declined to comment on the calibre of bullet casing while saying that it was collected as evidence and sent for forensic analysis. "The speed breaker area is the scene of the crime. But we don't any CCTV footage emerging from the area so far. It could provide vital clues as to how the constable sustained a hit. But the absence of CCTV footage has hindered the revelation. Some CCTV footage before the speed breaker area is available, and three were seen riding the bike. Saurabh was driving with two colleagues as pillion riders. No footage at the speed breaker area is available," said DCP (rural zone) Surendra Nath Tiwary. "The speed breaker is built by locals and is a bit on higher side. So, this led bike to become unstable. Noida police team told us that they didn't resort to any retaliatory fire to scare away the mob," the DCP added. Meanwhile, on Thursday night Qadir's brother, Adil, 22, was arrested from Wave City. The incident took place late on May 20 when a seven-member team of the Noida police arrived at Ghaziabad's Nahal village to arrest Qadir, whose name cropped up in a theft of a music system and car parts. A first information report (FIR) for theft was filed against an unidentified person at the Phase 3 police station on May 21. Ghaziabad police have maintained that they were not formally informed about the raid....