The National Investigation Agency (NIA) has registered an FIR in the October 8-9 clashes between two communities in Ekbalpur area of Calcutta, a senior official said.

The anti-terror agency is likely to start an investigation into the clashes from Wednesday and its officers may submit a copy of the complaint at Bankshall Court in the city, he said.

The NIA has taken over the investigation and registered the FIR on Tuesday.

"We are going to seek the custody of those arrested by Calcutta Police. We may seek video footage of the CCTV from the area. Our officers may reach the spot tomorrow," the officer told PTI when contacted.

The police had clamped Section 144 Cr PC in Ekbalpur till October 16 to maintain the law and order situation in the area.

So far over 45 people have been arrested in connection with their alleged involvement in the clashes.

The Calcutta High Court last week stated that it is for the central government's consideration, given the gravity of the incident, whether the probe is to be handed over to the NIA.