Some unidentified militants hurled a powerful grenade at the premises of an educational institute in Imphal west district of Manipur but it failed to explode, official sources said on Wednesday.
The militants lobbed the grenade at the complex of Little Mastern English School in interior Samurou village at around 9.30 pm on Wednesday night, they said.
Police today defused the grenade, sources said, adding that this was the second time the militants hurled the grenade at the school after May last month.
Earlier, after the May incident, school authorities had appealed to the people not to disturb the academic atmosphere in the school complex. Sources said police posts particularly in valley districts of Imphal east, Imphal west, Bishenpur and Thoubal have been frequently put on alert because of hurling of grenades and bombs at many places.
Police posts have also been asked to step up patrolling and checking of passers-by to intercept the movement of the armed ultras within their jurisdiction, sources said.