The dispute over the 165-km Assam-Mizoram border has its origin in British era demarcations and has since led to persistent conflict. Here is all you need to know about it:
In 1875, the first exercise to demarcate present-day Mizoram, then Lushai Hills, from the plains of Cachar in Assam was undertaken to introduce the inner line permit (ILP) regime. The British government demarcated the Lushai Hills under the Bengal Eastern Frontier Regulation of 1873. The regulation introduced the ILP regime in the northeast. ILP is a document issued for allowing the travel of an Indian citizen into a protected area for some time.
In 1933, the British conducted demarcations in the northeast for separate districts based on culture, linguistic and tribal lines. This led to a new boundary separating Lushai Hills, Cachar, and the former princely state of Manipur. As part of this trifurcation, some parts of Lushai Hills went to Manipur.
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Mizoram backs 1875 demarcation, saying it took place in consultation with then Mizo tribal chefs. Mizoram has rejected the 1933 demarcation saying Mizo tribal chiefs were not consulted then.
Assam backs the carving of districts in north-eastern states as per the 1933 demarcation.
In 1972, Mizoram was carved as a Union territory on basis of 1933 demarcation
When Mizoram was granted statehood in 1987, Mizo tribal leaders raised the border dispute claiming that Assam had taken away their land.
In 1995, the first major skirmishes were reported in Lushai Hills along the border when the Mizoram government tried to settle people there as per the 1875 demarcation. Nearly 50 persons, including journalists, were injured in action by Assam police in 2018 after some Mizo civil society groups tried to set up a hut on the disputed boundary.
In 2019, the two states agreed to maintain a status quo and have no man’s land in the disputed area.
Skirmishes in October 2020 left several injured on both sides and resulted in a blockade of National Highway 306, the lifeline to Mizoram, for 12 days.
Days before this clash, on October 9, similar violence took place on the border of Karimganj (Assam) and Mamit (Mizoram) districts.
Assam’s other border disputes
Assam also has border disputes with Nagaland, Meghalaya, and Arunachal Pradesh, the other states carved out of Assam.
Nagaland and Arunachal border dispute cases are pending in the Supreme Court.
Over 100 people have been killed, most of them on the Assam side, in attacks by armed men from Nagaland in separate incidents in 1979, 1985, and 2014.
The Meghalaya government informed the state assembly in 2020 that 56 incidents related to the border dispute with Assam have taken place since 2017.