Chief Metropolitan Magistrate Biswarup Seth remanded Hussain, a Bangladeshi national, who was arrested from near Kolkata Station yesterday, till July 16.
The accused was suspected to be involved in the German Bakery blast of Pune in 2010.
Public prosecutor Dipnarayan Pakrasi submitted before the court that Hussain was the main arms dealer for IM and also used to plan terror attacks.
Pakrasi submitted that he was a close associate of IM founder Yasin Bhatkal.
He stated that Rs 1.5 lakh in fake Indian currency notes, 30 bullets for AK-47 rifles, detonators, wires, batteries and some explosive substances, which were in a bag, were seized from Hussain at the time of his arrest.