Police said NIA officials took Ameerkhan, a mobile shop owner, into custody from his residence at Mettupalayam on information that calls from one of the five Sim cards he had sold to a man, Rahmathullah, had reportedly gone to the terror outfit.
He was asked to appear before NIA in Kochi on October 9 for further interrogation, they said.
The investigative agency also handed over summons to relatives of Rahmathullah, asking him to appear before the agency in Kochi, they added.