Under pressure from the Bhutan government, the United Liberation Front of Asom and the National Democratic Front of Bodoland may be shifting base to neighbouring Bangladesh.
The ULFA and NDFB have been based in Bhutan for the past decade and New Delhi has been mounting pressure on the government of the Himalayan kingdom to launch an offensive against them.
Sympathetic elements within the Bangladeshi army and the tacit support of Pakistan's Inter-Services Intelligence are seen as the two main reasons behind the choice of the new base.
In the past decade, both the ULFA and the NDFB had maintained camps in Bangladesh's Myemensingh district.
Intelligence agencies in the Northeast are keeping a close watch on the developments.
Based on their reports, the Centre is likely to request Dhaka to curtail the militants' activity and movement within Bangladesh.
Authorities have noticed a steady flow of arms and ammunition from the Himalayan kingdom into the Garo Hills (in Meghalaya) through a relatively unknown riverine route, BSF Inspector-General B K Dey said.
As a result, the Garo Hills region has of late become a hotbed of terrorists forcing Chief Minister D D Lapang to rush to New Delhi seeking additional paramilitary forces.
Security forces recently came across a large cache of arms in the area and a spate of encounters with militants has convinced authorities that the ULFA and the NDFB may be shifting base to Bangladesh via Meghalaya.
"Sophisticated weapons are being placed in boats and river rafts, which flow downstream on the Brahmaputra and reach Dhubri. These are collected at Gachpara and carried through dense forests to different parts of the Garo Hills region," Dey said.
The Union home ministry plans to insulate the frontier by reducing the distance between border outposts. It has ordered deployment of five additional battalions of the Border Security Force in the Garo Hills.
Some BSF battalions engaged in counter-insurgency operations in Manipur would be shifted to Meghalaya.
The movement of arms has not left the Garo Hills unaffected.
At least three terrorists of the ULFA and NDFB have been killed in the area in recent times.
On April 10, the West Garo Hills police shot dead a terrorist and recovered 96 rocket-propelled grenades, a large amount of RDX, arms and ammunition.
On Saturday April 12, the army, the Central Reserve Police Force and the Meghalaya police began a joint operation to bust ULFA hideouts in Phulbari town.
According to police sources in Meghalaya, the Achik National Volunteers Council, a 10-year-old terrorist outfit, has teamed up with the National Democratic Front of Bodoland, which mainly operates in western Assam bordering Garo Hills, to spread terror in the area.
Last week, ANVC terrorists abducted four Bengali-speaking traders from Chibunang Bazaar, 5km from the Phulbari police station in West Garo Hills district.
Earlier, the ANVC had abducted two government officials from Baghmara in South Garo Hills district.
The fate of PWD engineer Jatindra Bhattacharjee and Deputy Inspector of Schools Pobitra Hajong is still unknown.
They were adducted on the day militants released a customs inspector Deepak Mahanta and three coal traders, who were in their custody for over a fortnight.
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