Police in Bangladesh has said that a secular blogger has been hacked to death in north-eastern part of the countr.
This is the third such deadly attack since the start of the year.
Mr Das wrote blogs for Mukto-Mona, a website once moderated by Avijit Roy, himself hacked to death in February.
He was killed in a machete attack while he was visiting the Bangladeshi capital, Dhaka, as he returned with his wife from a book fair in the city.
His widow suffered head injuries and lost a finger.
And in March, another blogger, Washiqur Rahman, was hacked to death in Dhaka.
Sara Hossain, a lawyer and human rights activist in Dhaka, has told the BBC Mr Das and Mr Roy were on a list of targets.
"These last two have been part of a blog called Mukto-Mona (Free Mind), which is about free thinking and is about explicitly taking on religious fundamentalism and particularly Islamic religious fundamentalism. Their names have been on lists of identified targets."
The attack on Mr Roy prompted massive protests from students and social activists, who accused the authorities of failing to protect critics of religious bigotry.
An Islamist has been arrested over his murder, while two madrassa students have been arrested over Mr Rahman's killing.
