The Polit Bureau said media reports that there were warnings of a possible attack in Pune "are disturbing as these attacks have taken place despite this."
In a statement, the party said it was imperative in the interests of the country's security that such lapses were rectified urgently.
The Polit Bureau called upon the Central government to provide assistance to Maharashtra to "identify the culprits."
It also conveyed its condolences to the families of victims and wished the injured a speedy recovery.
Bring out truth: CPI
The Communist Party of India demanded that the government bring out the truth behind the blast and expose those responsible for it.
Its national secretary D. Raja said the government should speak through its actions and not indulge in rhetoric stating that there was no intelligence failure.