"We firmly disapprove the violence and killings to gain political power in a democratic country," CPI National Secretary D Raja said.
Referring to the Salwa Judum movement, he said "Maoists must not resort to the politics of vendetta and revenge killings".
While offering condolences to the bereaved families, he also appealed to all sections of people to maintain peace.
Heavily-armed Maoists ambushed a convoy of Congress leaders in Chattisgarh's Bastar district yesterday, killing 27 people including senior Congress leader Mahendra Karma, and injuring 32 others.
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