Recent spike in infiltration of terrorists from the eastern sector to India has rung alarm bells in the security establishment. There has been three-fold increase in infiltration by Harkat-ul-Jihadi al-Islami (HuJI) and Jamaat-ul-Mujahideen Bangladesh (JMB) extremists into the border states of West Bengal, Assam and Tripura according to the report from the Bangladesh government to the Union home ministry. The development assumes significance as the NIA has found overseas terror links and the direct role of JMB in the October 2014 Burdwan blast at Khagragarh in which two suspected terrorists were killed. Approximately 2,010 HuJI and JMB operatives had entered the three states. While nearly 720 men made a safe passage through the Bengal border, the remaining 1,290 are suspected to have entered through Assam and Tripura. The number of infiltrators in 2014 and 2015 stand at 800 and 659, respectively and in Assam around 54 JMB operatives were arrested in the last six months which is a serious matter. These infiltrations in some cases are done with the help of fake papers and once they reach India contact is established with linkmen in Assam and Bengal. Some of them may also visit Delhi. There has been a change in the operational mechanism of these militants post-Khagragarh blast and this was creating problems for security agencies in tracking them. Previously the infiltration was carried out from some porous districts like Malda, Murshidabad or Nadia and now the entry point has been shifted to through Assam and Tripura and then entering West Bengal. Being a riverine border, it is difficult for security agencies to keep vigil all along but it makes easier and safer for them to cross over. New Delhi never gave importance to influx from eastern sector compared to western and northern sectors. Assam is vulnerable to terrorist attack because of its natural resources like oil, gas and minerals.