DHAKA, BANGLADESH - FEBRUARY 27: Bangladeshi social activists shout slogans as they participate in a torch rally held to protest against the killing of Avijit Roy in Dhaka, Bangladesh on February 27, 2015. Roy, a prominent Bangladeshi-American blogger known for speaking out against religious extremism was hacked to death as he walked through Bangladesh's capital with his wife, police said Friday. (Photo by Zakir Hossain Chowdhury/Anadolu Agency/Getty Images)

DHAKA, BANGLADESH - FEBRUARY 27: Bangladeshi social activists shout slogans as they participate in a torch rally held to protest against the killing of Avijit Roy in Dhaka, Bangladesh on February 27, 2015. Roy, a prominent Bangladeshi-American blogger known for speaking out against religious extremism was hacked to death as he walked through Bangladesh's capital with his wife, police said Friday.  (Photo by Zakir Hossain Chowdhury/Anadolu Agency/Getty Images)