Low intensity explosive devices were used to set off the three blasts at a Malegaon mosque on Friday, a senior Maharashtra police officer said.
It is learnt that the explosives were detonated by a mechanical or a digital timer.
"Many of the injured have splinter injuries, indicating that explosive devices similar to timer-fitted crude bombs could have been used, the official said.
"There were definitely timer-fitted devices and evidence at the moment suggests that an analogue or a digital timer may have been used," he added.
Anti Terrorism Squad Chief K P Raghuvanshi ATS DIG Subodh Jaiswal and other squad members are camping in the town to ascertain the nature of explosives.
Samples of the explosives have been sent to the forensic science laboratory in Mumbai, where tests to identify the explosive were likely to be completed by Saturday evening, sources said.
ATS sources were non-committal on whether RDX was used -- even in minute quantity.
"We suspect the that RDX that was being transported by suspected Lashkar-e-Tayiba members near Aurangabad, a portion of which was seized in May, has still not been fully seized.
It cannot be ruled out that some of that may have been used yesterday,", an ATS official said.