Avijit Roy, known for his critique of religious extremism, was hacked to death in Dhaka by machete-wielding assailants who attacked the Bangladeshi-origin writer as he was returning from the book fair with his wife on Thursday.
The decision to send the FBI team came after the Bangladesh government accepted America's offer to engage them in the investigation process, bdnews reported.
"The FBI will deploy a small team to Bangladesh shortly to assist and collaborate with Bangladeshi law enforcement agencies to investigate the homicide," said Monica Shie, US embassy spokesperson in Dhaka.
The FBI would be able ‘to provide technical assistance with regard to transnational aspects of the investigation.’
The elite Rapid Action Battalion on Monday arrested Farabi Shafiur Rahman, a self-proclaimed Islamist blogger who had previously threatened Roy multiple times.
"Avijit's father mentioned Rahman's name as he had threatened to kill his son several times," Commander Mufti Mahmud Khan, director at Legal and Media Wing of the RAB said.
"A year ago Rahman threatened to kill Avijit Roy, one of the founder moderators of a popular blog Mukto-Mona," he said. On January 25 last year, Rahman's Facebook status read, "It's a holy duty of Bangalee Muslims to kill Avijit."
Then on February 9, last year, he commented on a Facebook post: "Avijit Roy cannot be killed now. He lives in America." A court on Tuesday remanded Rahman in custody for 10 days for questioning.
"He has confessed that he threatened Avijit Roy. Intense interrogation of Farabi could lead to important clues," Dhaka Metropolitan Police spokesman Monirul Islam said.
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