In capital Shillong, chief minister Mukul Sangma unfurled the national flag and took the salute at a ceremonial parade.
"The government will continue to follow its policy of zero tolerance to criminal activity by any group," Sangma said.
Congratulating the people for taking a tough stand against militancy, he said: "I firmly believe that it is the strong will of the people that will enable the government in eradicating the menace of insurgency from the state."
Urging the insurgents to surrender and join the fight against hunger and poverty rather than playing into the hands of anti-national elements, Sangma said: "Our government has kept an open mind in dealing with militant outfits. I am aware that a number of our young men are drawn into these outfits under compelling situations."