Official sources said today that the militants asked the owners of "Ibochou Petrol Service" and "Emo Filling" to close down their pumps yesterday, failing which they would face dire consequences.
Sources close to the pumps said a huge amount of money was demanded by some suspected militants from the two pumps which the the owners could not pay.
No individual or group has claimed responsibility for the act.
In other incidents, suspected militants hurled a grenade at a private hospital, Shija Clinic, here last evening and another one at the house of a resident in Thoubal district last evening.
The grenades were later defused by the bomb experts, sources said.
Non-payment of money appeared to be the motive behind the hurling of the grenades.