The militants came on a two-wheeler and hurled the bomb at Singh's house in Lamlai area at 7:45 PM, the sources said.
The bomb exploded but nobody was injured in the explosion, they said.
Singh and his family members were not present in the house at the time of the explosion as they stay in his official quarter at Imphal.
No individual or group has claimed responsibility, they said, adding, police forces rushed to the spot.