Police said the Naxals triggered the blast between Cholnar and Kirandul villages when a joint team of the Chhattisagarh Armed Force and the District Force, in an SUV, was escorting a vehicle carrying material for road construction work.
Among those killed, four personnel belonging to the Chhattisgarh Armed Force (CAF) and Three to the District Force (DF).
Naxals looted six automatic weapons -- two AK-47s and as many INSAS and self-loading rifles -- of the deceased personnel. Reinforcement was rushed to the spot soon after the incident.
Inspector General of Police (Bastar) Vivekanand Sinha said: "We have sounded a high alert in the area and launched a search operation for the Naxalites."
Road construction work is underway between Kirandul and Palnar villages in Dantewada.
(With inputs from agencies)