It was learnt that the agency was inquiring into the movements of the duo and from where they had bought the material used for making explosives.
IndiGo on Monday started flight operations from the Darbhanga airport in Bihar to expand its regional presence.
Mohammad Salim Ahmed and Kafil, both residents of Kairana in Shamli district of UP, would be produced before a special NIA court in Patna after obtaining a transit remand from the competent court.
The case was originally registered at Railway PS Darbhanga, Bihar relating to an explosion in a parcel on Platform 1 of Darbhanga Railway station on June 17.
The parcel was booked in the name of Mohd Sufiyan by Sufiyan himself, which contained seven packets packed with sarees.
The key conspirators in the case, who belong to Shamli district of Uttar Pradesh, were residing at Nampally in the city.
A plant generating medical oxygen at Darbhanga abruptly broke down on May 5 creating a life and death situation for 500 patients.
Upon knowing that Rai had tested positive for the virus, most of his relatives distanced themselves from the family fearing the spread of the infection.
State minister Sanjay Kumar Jha came out with a flurry of angry tweets in response to a twitter post by Chidambaram who had referred to a television news report on Bihar's hospitals.
BJP leaders probe a murder in Bihar, say man was indeed killed because he named site after PM Narendra Modi
Union minister Giriraj Singh, Bihar BJP president and MP Nityanand Rai and MLA Sanjay Sarawgi were among ten senior leaders of the state’s ruling BJP who visited Bhadwa village.
Three persons have been arrested in connection with beheading of the father of a BJP worker in Darbhanga, even as police asserted that the killing was the fall-out of a land dispute.