Recalling the 2011 ethnic clash between the Garo and Rabha communities, Sangma said people are being taken for a ride, and manipulated by many vested interests.
"It was painful. Members of the communities, who have been living with each other, started fighting each other.
"They forgot traditional values," Sangma said in his inaugural address at an international seminar on cultural heritage and peace education organised by Unesco here.
"During the last elections, I would always say a prayer, that is to bless my people with knowledge, wisdom and enlightenment so that they may not be manipulated," said Sangma.
The chief minister, otherwise known as a stern political leader, broke down before hurriedly returning to his seat at the convention centre.
Sangma lamented the gradual collapse of peace and harmony.
"The tenets of tolerance, traditional and moral values, love, compassion, and harmony were strongly upheld by forefathers, but people have forgotten these traditional values," he said.
He came down heavily on politicians who attempt to infuse a sense of insecurity into the minds of people.
"Political leaders make speeches where they try to talk about their own communities and infuse a sense of insecurity in the minds of the people, thereby creating a divide and a situation, which is fertile for any kind of communal hatred," Sangma said.
Sangma underscored the importance of education to keep communal hatred at bay.
"When people are educated, they will know how to insulate themselves from being manipulated," he added.