In Assam, security forces have arrested four suspected militants of National Democratic Front of Bodoland, NDFB, today in Udalguri district. Acting on a tip off, security forces also recovered four AK-A7 rifles and other ammuniation. Official sources said in Guwahati police and army have intensified operation to seize all illegal arms and explosives across the state. Two more persons have been picked up linkmen for questioning . Maximum alert has already been sounded in the state .