Separate groups of Maoists on Monday night went to a middle school at Newari village and a primary school at Bhargaon village and packed explosives there before triggering the blasts, they said.
There were, however, no reports of any casualty in the twin incidents. A patrolling squad, meanwhile, recovered two landmines weighing 25 kg each hidden at a place in Meral Middle school in Latehar district.
Police said the explosives were meant to blow up this school too. In Gumla, security forces found a 15 kg landmine planted on the Kurumgarh-Bamda road under Chainpur police station, police said.
While Gumla goes for polling in the fourth phase on December 12, Latehar is going for polls in the fifth and final phase of polling scheduled on December 18.
Maoists have a track record of blowing up schools to prevent security personnel from taking shelter during anti-Naxal operations.
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