However, no casualty was reported, they said.
Unidentified miscreants triggered an Improvised Explosive Device (IED) at Moreh ground in the border town in Chandel district late last night, police said.
Another grenade explosion was reported early this morning at the gate of the residence of one Wahengbam Shamu Singh at Singjamei Chingamakha in Imphal West district, police said adding that the reason behind the blast was yet to be ascertained.
Investigations were on, police said.