Sources told rediff.com that the bomb, which was attached to a battery, was low in intensity.
The explosion takes place a day ahead of the elections.
Sources say it is too early to say whether it was the handiwork of a terror outfit.
It could be a blast with a political angle to it, sources point out.
Madhubani has had a tryst with terror only when it was found that there were recruitment camps here.
As per an intelligence dossier, Madhubani along with Araria and Sithamarhi were used as recruiting grounds.
Investigations are on to ascertain the nature of the blast, but at the moment the police are ruling out a terror strike.
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