Militancy is not the only major reason that has kept the Northeast troubled for decades.
'Seven Sisters,' as the Northeastern states are referred to are often found fighting on their inter-state borders like the one along Assam-Mizoram border on Monday in which six Assam policemen died and 42 others injured.
From killing of 41 persons in 1985 at Merapani in Assam's Golaghat district bordering Nagaland to the firing on Mizoram border and the skirmishes at the Assam-Meghalaya border on the outskirts of Guwahati on Monday, the conflicts on the border have often taken violent turn and kept the states on their toes.
Assam is facing a border dispute with Nagaland, Mizoram, Arunachal Pradesh and Meghalaya, while Tripura and Mizoram too are facing similar issue for long.
The origin of the disputes regarding the borders dates back to the pre-Independence era and even till 1972 when Meghalaya and Mizoram were carved out of Assam. Mizoram was first became a Union Territory and was made a full-fledged state in 1986. Nagaland, which has been witnessing insurgency since the Independence, was granted statehood in 1963. Arunachal Pradesh, which was known as North East Frontier Agency became a state in 1987, last among the 'seven sisters'.
The Northeast remained untouched during reorganisation of the states and the territories along linguistic lines, which, according to experts, made the situation more complex.
The disputes became acute due to conflicting claims over their border by the states and the Centre's inability to convince the states to accept the boundaries.
Assam insists that the boundaries marked after Independence be maintained, while states like Nagaland and Mizoram stress on "historical boundaries" dating before it. Mizoram demands that the 164.6 km border with Assam be decided based on Bengal Eastern Frontier Regulation, 1875.
Tension on Assam-Nagaland border is also often witnessed even as a petition is pending in the Supreme Court.
Assam and Meghalaya Chief Ministers met on July 23 and pledged for extra efforts to take the border issue from status quo towards a permanent solution. There are 12 areas of conflict between the two states.
On Sarurday, Home Minister Amit Shah, who met Chief Ministers of Northeastern states in Meghalaya capital Shillong stressed that the border conflicts be resolved amicably before 2022 when the country celebrates 75 years of Independence. Two days later, the violence erupted along Assam-Mizoram border.
"What transpired in the meeting between Shah and the CMs? The BJP government should tell the people, who are suffering on the border. Why can't they solve the disputes when states in the region are either ruled by BJP or their allies?" Assam Pradesh Congreas Commitee spokesperson, Bobbeeta Sharma asked.
Assam CM, Himanta Biswa Sarma, when asked about Congress' questions, on Tuesday said, "This is not a political issue. This is a conflict between two states. Why did Congress not solve the issue when they were in power in all states of the Northeast?"