The cadres of the Joint Madhesi Front protesting against the federal model proposed by Nepal's major parties also set ablaze two police posts in the Birgunj municipality which borders Bihar's Raxaul town.
Nepal has seen several violent protests in recent weeks against the new draft Constitution with the unrest claiming 11 lives including seven police officers and a 2-year-old child.
The drafting process has been halted due to the protests launched by Madhesis in southern Nepal and Tharu community in western Nepal protesting against the proposed seven-province model of the federal structure to be incorporated in the new Constitution.