The autopsy of the victims showed that the impact of the explosion was felt more in 2007 than it is now though the victims had similar injuries, the expert, who was involved in both the investigations, said.
“Iron particles were found inside the bodies of the victims. We found nuts, bolts, nails, pieces of glass then and also now,” the said.
In the twin blasts that hit Dilsukhnagar area of Hyderabad yesterday, 16 people were killed and 120 injured.
45 people lost their lives in bomb blasts that occurred at the Lumbini Park and Gokul chat shop here in 2007.
A "highly-disturbed" crime scene has not helped police make much headway into the twin bomb blasts probe at Dilsukhnagar here even as special teams from NIA, NSG and the Central Forensic Science Laboratory collected samples and sent them for detailed analysis.
The Saroor Nagar police registered a case, based on a complaint by eye-witness Gadagolla Anand, under different sections of IPC and Sections 3 and 5 of the Explosive Substances Act as well as Sections 16, 17 and 18 of Unlawful Activities (Prevention) Act on the twin blasts in which 16 people were killed and 119 injured.
"The crime scene was largely disturbed as large number of people moved freely even before we could totally sanitize the two spots," an Inspector General of Police, who was among the first to reach the spot last night, said.
"A lot of evidence virtually got trampled due to movement of VIPs, including the Chief Minister, large number of media personnel and curious onlookers.But still we could gather some material that could help us in the probe,'' he said.
"It was a high-grade explosion but the quantity of explosive used was low as it was an improvised explosive device.There was no conclusion yet about the type of explosive used in the blasts. There are still many loose ends in the case which we are trying to tie up.
He said police is examining video footage recorded on closed-circuit cameras, installed at the Dilsukhnagar bus stand junction (Rajiv Chowk) and also at one of the bus shelters in the vicinity.
Sleuths from the Crime Investigation Department joined their other colleagues in carrying the investigation forward even as special teams constituted by the state police started scouring for clues across the city.
"The fast food centre where the blast occurred is always bustling with customers, mostly students, as there are a good number of coaching institutes in the locality. Some students had just come for tea last night when tragedy struck," Dwarakanath, who works in a shop on the other side of the road, said.