This means the explosion that targeted the Congress convoy was precisely timed and manually controlled.
While security personnel checked the route for explosives and landmines four hours before the strike, the Naxals placed them barely two hours before the convoy was scheduled to arrival.
Nearly 30 kg of explosives, containing ammonium nitrate and heavy metallic components, made a significant impact at the site.
Investigations have revealed that the strike was carried out by the Andhra-Orissa command of the left-wing ultras. The masterminds behind the attack, including K Sudarshan and his deputy Gaganna, were all members of the erstwhile Peoples' War Group.
The Naxals were aware of the schedule of he Congress convoy, including its decision to change the route at the last minute based on a suggestion by a local leader.
The Naxals were getting constant updates about the movement of the convoy and the information helped them carry out the explosion to stall the vehicles, according to the probe.
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