"I have spoken to Raman Singh and he has agreed for probe by NIA and he has agreed to the probe by the central agency," Union Home Minister Sushilkumar Shinde said on Monday.
Shinde said he has asked Union Home Secretary R K Singh to proceed accordingly in the matter.
Shinde added that he has briefed Prime Minister Manmohan Singh about the decision to hand over the investigation to the NIA.
Heavily-armed Maoists had on Saturday night ambushed a convoy of Congress leaders in Chhattisgarh's Bastar district, killing 27 people, including Congress leader Mahendra Karma, Pradesh Congress Committee chief Nand Kumar Patel, his son Dinesh and former Member of Legislative Assembly Uday Mudliyar.
Thirty two others, including former Union minister V C Shukla, were injured in the attack.
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