"Brigadier T Sailo's demise is deeply saddening. He will be remembered as a multifaceted personality who worked for Mizoram's progress," Modi tweeted.
Sailo passed away in Aizawl here today at the age of 93 after heart failure.
He had formed a political party called Mizoram Peoples Conference in April 17, 1975 and it won the Mizoram union territory elections in 1977 and he became the second chief minister of the state.
He was elected to the state assembly in 2008 for the last time and quit active politics at the age of 92 after his term ended in 2014.
He described Kyndiah as a popular leader who worked tirelessly for Meghalaya and the northeast.
Kyndiah passed away at a hospital in Shillong following cardiac arrest today. He was 87.