He, however, asserted that all infiltrators will be thrown out of the country.
Prime Minister Narendra Modi will sharpen Bharatiya Janata Party's campaign for the high-octane assembly elections in West Bengal with a mega rally at the Brigade Parade Grounds in Kolkata on Sunday.
A fresh political row has erupted in West Bengal over Bharatiya Janata Party national vice-president Dilip Ghosh's alleged unsavoury remarks about West Bengal Chief Minister Mamata Banerjee, with the Trinamool Congress seeking his arrest and unconditional apology.
Both private and government hospitals have joined the protest, fighting for justice for the victim and demanding a security act for doctors.
Shah, while releasing the saffron party's manifesto 'Sankalp Patra' for the upcoming assembly elections in Jharkhand, announced that a Displacement Commission would be formed to ensure rehabilitation of people displaced by industries and mines in the state.
The 34-year-old TMC national general secretary was seen entering the new office of the central probe agency in central Delhi around 11 am.
CPI-M General Secretary Prakash Karat spoke briefly to rediff.com's Sheela Bhatt on the party's prospects in the coming assembly elections in Kerala and West Bengal.
Chatterjee, who was the state education minister when the scam took place, was arrested after around 26 hours of grilling in connection with the probe.
Opposition MPs on Tuesday demanded the resignation of Manipur Chief Minister Biren Singh over the violence.
The bypoll on September 5 is also a litmus test for all three political outfits, with the BJP hoping to check its erosion in its vote share and retain the seat, the TMC aiming to wrest the tribal-dominated assembly segment and the CPI(M)-Congress alliance hoping to regain its traditional seat.
Expressing concern over agitation by Trinamool Congress workers outside the Central Bureau of Investigation office in Kolkata and elsewhere in West Bengal after the arrest of two ministers and others in the Narada sting case, Governor Jagdeep Dhankhar on Monday alleged that there is 'total lawlessness and anarchy' in the state and the police and administration are in 'silence' mode.
BJP chief Amit Shah had set a target of winning 22 Lok Sabha seats out of 42 seats in West Bengal.