The packing of the improvised explosive device with RDX, used in the blast at Pune's German bakery has left forensic experts flummoxed as they were unable to find any remnant to identify the circuit used for detonating the bomb.

    
The explosive material -- RDX and Ammonium Nitrate --does not have the signature of earlier blasts, including in Ahmedabad, Bangalore and Delhi and the "packing" of explosive material is of such a high quality that even forensic experts have not been able to pick a single clue about its timer.

     
The three forensic teams -- State Forensic Laboratory of Mumbai, Gandhinagar and CFSL --

     
The forensic experts admit this time there was a better execution by the terror module and the profile of the explosive material was different with majority of IED comprising RDX with Ammonium Nitrate used to gel with engine oil to cause fire, the sources said.

Pune Police Commissioner Satyapal Singh had said "it was a mixture of RDX, Ammonium Nitrate and Petroleum Hydrocarbon oil that set off the blast."