A police spokesperson said the bomb exploded near the entry gate of the ongoing Sangai Festival around 11 a.m.
"We suspect the person who died is the one who carried the bomb concealed in a sack to plant at the festival venue," a police official said requesting not to be named.
The bomber was apparently riding a cycle rickshaw when the blast took place.
"Today was the concluding day of the festival and there were no people around when the blast occurred and hence there no other casualties," the official said.
Police are yet to identify the bomber.
The blast comes ahead of Prime Minister Manmohan Singh's daylong visit to Imphal Dec 3 when he is scheduled to launch and inaugurate several development projects. The prime minister is also expected to address a public meeting.
There are over 20 militant groups active in Manipur, bordering Myanmar, with demands ranging from secession to greater autonomy.
