The roots of the massacre reach back to 1947. After Partition, waves of Bengali Hindu refugees fled Muslim-majority East Pakistan -- later Bangladesh -- and settled in Tripura, then a princely state merging into the Indian union. The influx was enormous. Over the following decades, the Tripuri people, who had formed the majority in their own territory for centuries, became outnumbered by Bengali settlers. Economic tensions followed demographic ones: the newcomers dominated commerce and the professions while indigenous communities were pushed to the margins. Tribal insurgent groups formed, driven by a potent mix of dispossession and ethnic nationalism. By 1980, Tripura was, as journalist Subir Bhaumik later described it, "a hotbed of violent political action where the ruling hammer and sickle is being challenged by tribal insurgency, saffron nationalism and Bengali subnationalism."

The violence did not erupt spontaneously. On the night of 6 June 1980, armed insurgents began cordoning off nontribal localities across the Jirania block, following what survivors described as a blueprint of coordinated destruction. By morning, reports of arson, looting, and murder were spreading across the region. Thousands of Bengali families fled toward National Highway 44. The Block Development Officer of Jirania opened a relief camp at Khayerpur School, and Shankar Narayan, the district magistrate of West Tripura, ordered provisions for the refugees. But the army units dispatched to the area were given orders only to conduct a flag march -- a show of presence without intervention. In the Bengali villages in the foothills of the Baramura range, homes burned while soldiers walked past.

At 3:00 a.m. on 8 June, Satyendra Chakraborty, the LAMPS manager of Mandai, and Sachindra Saha, a CPI(M) leader, arrived at the Block Development Office to report that over 500 Bengalis in Mandai had been surrounded by armed Tripuri fighters. Many residents had taken shelter at the village police outpost -- which they found unmanned. No constable was present. No defense was organized. When a contingent of the Rajasthan Armed Constabulary and a platoon of Tripura Armed Police finally set out from Jirania at 6:00 a.m., they found the village of Purba Noabadi engulfed in flames along the way. After stopping to extinguish the fire, they continued to Mandai. By the time they arrived, every house and hut had been reduced to ash except for the LAMPS building.

Official figures placed the death toll at 255. Foreign press outlets and eyewitnesses described scenes of far greater carnage and put the count between 350 and 400. The injured were loaded onto a truck and transported to GB Hospital in Agartala. Survivors were dispersed across the city's schools for shelter. Curfews blanketed the state for months. On 8 July 1980, the Ministry of Home Affairs established the Dinesh Singh Committee to investigate the massacre. The ethnic riots that followed the initial attack claimed more than 1,000 additional lives across Tripura, the vast majority of them Bengali. In the decades that followed, insurgent violence continued to plague the region: over 6,000 people died in attacks by various rebel groups in the early 21st century, and more than 500 were kidnapped for ransom.

Many Bengali families left Mandai permanently. Those who stayed or returned found a landscape scarred by what had happened and by the insurgency that continued until 2009. The village that once appeared in the land records under a misspelled name became a byword for the unresolved tensions of India's northeast -- a region where Partition did not end with a border drawn on a map but continued to play out in villages, in demographic shifts, in cycles of displacement and retaliation. Mandai's story is not about a single night. It is about the slow accumulation of grievances on all sides -- indigenous dispossession and settler vulnerability, military inaction and political failure -- that made such a night possible and that have never been fully addressed.