Three men died and six were injured on Sunday in two separate explosions in Kathmandu, Nepali police said.
There was no immediate claim of responsibility but police said they suspect involvement of a Maoist splinter group whose pamphlets were found in a house where one of the explosions took place.
A powerful blast inside a shop killed two people and injured five, while the explosion at the house about 4km away left one dead and another injured.
"We are investigating both incidents," Police spokesman Bishwa Raj Pokharel told AFP.
Nepal has enjoyed a relatively peaceful environment since the end of a decade-long civil war which concluded with a peace deal struck in 2006.
But some former guerrillas, have broken away, accusing its leaders of betraying their original revolutionary ideals.
In February, the same Maoist splinter group was implicated in an explosion that killed one person outside the office of a telecom company Ncell, part of Malaysia-based Axiata Group Berhad.
The government outlawed the group following the incident, banning their activities.