The violence began on Sunday in a village in Sunsari district after an argument between Hindu and Muslim residents during a religious procession. 

The dispute reportedly started over loud music and the display of religious flags.

Police said two people were killed after security forces opened fire to control the situation. 

Another person later died during protests in neighbouring Siraha district after demonstrators violated a curfew. 

Nepal's Prime Minister Balendra Shah has urged people to remain calm and act responsibly.