An expert on Sunday said the explosives used in Saturday's twin blasts and the Mecca Masjid attack on May 18 were different.

"In the Mecca Masjid blasts, it was a RDX and TNT mixture. Here, it is entirely different (as some) ammonium nitrate-based chemical (was used)," T Suresh, chief scientific officer of the CLUES bomb detection squad of Andhra Pradesh, told NDTV news channel.

Three months ago, pipes filled with explosives triggered the blasts at Mecca Masjid, he said.

Referring to the bomb that was defused in Malapadda area on Saturday night, Suresh said experts found that Neogel-90, an ammonium nitrate-based explosive, was used in it.

"That chemical is mixed with small metallic iron balls (and the device) is connected to an alarm clock and detonators connected to a battery," he said.

In the case of the blast at Gokul Chat Bhandar, he said the bomb was placed on an ice cream machine, about five feet above the ground, to cause greater impact.