Dhaka Metropolitan Police Assistant Commissioner Nurul Amin said at least three men riding on a single motorbike carried out the killing Wednesday night. No group immediately claimed responsibility.
Police suspect 28-year-old Nazimuddin Samad had been targeted for his outspoken atheism in the Muslim majority country, and for supporting a 2013 movement to demand capital punishment for war crimes involving the country's independence war against Pakistan in 1971.
The killing follows a string of similar attacks last year, when at least five secular bloggers and publishers were killed allegedly by the radical Islamists.
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