"These incidents are the handiwork of elements trying to create disturbances in the country," Singh said in a statement here.
"We should condemn such acts as are being carried out by the forces inimical to peace and tranquillity and are aimed at creating an atmosphere of fear in the country," he added.
Singh said these forces would be strictly dealt with so that these violent incidents do not reoccur.
He appealed to the people of the state to maintain their century-old brotherhood and amity.
The terrorists killed eight persons -- three civilians, Superintendent of Police (Detective) Baljit Singh, a Punjab provincial service officer, two home guards and two policemen. The toll may go up as some of the 15 injured were in a serious condition.
All the three militants were killed in the exchange of fire with security forces at an abandoned building adjacent to the Dinanagar police station.