Investigators re-visiting the 2006 Malegaon bomb blasts probe following the reported confession of Swami Aseemanand have found forensic evidence that links those bombs to the explosives used in Hyderabad?s Mecca Masjid and the Ajmer Dargah in 2007.

The evidence had been with the Maharashtra anti-terrorism Squad and the CBI which subsequently took over the probe, but it could not be connected to Mecca Masjid or Ajmer as the two came much later and those investigations were handled by different agencies, sources said.

But following Aseemanand?s reported confession last month that Hindu extremists may have been responsible for the 2006 Malegaon blasts as well, a Special MCOCA court allowed the CBI to re-investigate the case. The 2006 Malegaon bomb, sources said, had been built with inter-threaded twin cast iron pipe shells just as the bombs used in Mecca Masjid and Ajmer. Remnants of the pipe were recovered from the scene of the blasts in 2006 but could not be connected to other blasts in the country as it was the first time such a pipe had been used, the sources said.

?Cast iron is used in India only by the Army,? said one forensic expert who has studied the remnants of all the bombs at the 2006 and 2007 blast sites linked to Hindu extremists. ?The metallic striations inside these pipes match the striations of the grenades used by the Indian Army.?

The white RDX used in the 2006 bombs was also the same as the RDX used in the subsequent bombs blamed on Hindu extremist groups, whose alleged link in the Indian Army was discovered following the arrest of Lt Col Shrikant Prasad Purohit after the 2008 Malegaon blast.