Bhatkal and his close aide Asadullah Akhtar, arrested from the India-Nepal border, were presented in the court here under tight security.
District Judge I.S. Mehta granted the NIA extended custody of Bhatkal after it said he was involved in subversive activities of causing bomb blasts in different parts of India since 2003.
"I have perused the case diary and am satisfied that the accused Mohd. Ahmed Siddibappa alias Yasin Bhatkal is required for interrogation. The accused Yasin Bhatkal is remanded to police custody up to Sep 22," the judge said.
The NIA, seeking custody of Bhatkal, said: "The objective of the investigation of the case is primarily to uncover each and every aspect of the activity of IM and their hidden sleeper cells and operatives so that the number of terrorist activities being planned by the outfit could be prevented."
The agency also told the court that Bhatkal had associates in Pakistan, Nepal and Middle East who were also involved in the case and more information regarding them has to be ascertained during his custodial interrogation.
The agency's Hyderabad unit moved a separate plea seeking permission to formally arrest Akhtar in connection with the Feb 21 blasts in Hyderabad's Dilsukhnagar area. The court allowed the plea.
The twin blasts, which claimed 16 lives, were triggered by IEDs planted near Konark and Venkatadiri theatres in Dilsukhnagar area.
Bhatkal tops the Delhi Police list of 15 most wanted terrorists involved in bombings across the country.
He is a key suspect in the 2008 serial bombings in Delhi's Connaught Place, Ghaffar Market and Greater Kailash areas which claimed 26 lives and injured 133 people.
--IANS (Posted on 17-09-2013)