The three militants of Ansarullah Bangla Team were detained last night from Dhanmondi and Nilkhet areas, Major Maksudul Alam, deputy director for Rapid Action Battalion's legal and media wing, said.
The detainees were identified as Touhidul Islam, the mastermind of Avijit Roy and Ananta Bijoy Das killings, and group's active members Sadek Ali and Aminul Mollik, The Daily Star reported.
Ansarullah Bangla Team, Bangladesh chapter of Al Qaeda in the Indian Sub-Continent, was banned in May over a spate of killings of bloggers.
Assailants in February had killed 45-year-old Roy, a Bangladesh-born US national, here while his wife narrowly escaped the attack.
Machete-wielding masked men in May hacked to death 33-year-old Das.
Apart from Roy and Das, two other bloggers killed this year are Niloy Chakrabarty Neel and Washiqur Rahman.
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