The para military forces posted at Moirang and Sendra used to jog in the area almost daily.
The sources said seven personnel were wounded in the explosion and one of them - Naik subedar Nivesh Rao -succumbed to his injuries at the army hospital at Leimakhong. Six others sustained splinter injuries and the condition of two of them was stated to be critical.
The area was surrounded and all its exit points were blocked by a police contingent aided by security forces before a search operation was launched to nab the insurgents, they said.
With no arrest made so far, the sources said the insurgents might have escaped to nearby thick jungles after planting the bomb at the roadside in the early hours. No individual or insurgent group has claimed responsibility for the blast so far.
The banned Revolutionary People's Front (RPF) had earlier announced that it would intensify its strikes against security personnel in near future.
Activists of the People's Liberation Army (PLA), armed wing of the RPF, had yesterday blasted a bomb at Tiddim area in Imphal West district injuring an jawan and a civilian.