A prominent Bangladeshi-American blogger, who wrote against religious fundamentalism, was hacked to death in Bangladesh's capital.
Avijit Roy, a Bangladesh-born U.S. citizen, and his wife, Rafida Ahmed, were attacked late Thursday after leaving a book fair at Dhaka University, authorities said. Ahmed, who is also a blogger, was seriously wounded.
The incident was the latest in a series of attacks on secular writers who have supported freethinking values in predominantly Muslim Bangladesh in recent years.
In reacting to Roy's murder, Bangladeshi human rights activist Adilur Rahman Khan said, "People who believe something different, who are independent thinkers - they are getting attacked - they are prosecuted and put in jail.”
Khan, who received the 2014 Robert F. Kennedy Human Rights Award, described the situation as very serious.
"This is a situation where the rule of law does not exist. And this kind of situation is happening. And this is really deplorable and Bangladeshi people are feeling they are helpless at this stage," he said.
Kazi Shawkat Ara, a schoolteacher who witnessed the attack, described the scene as horrific and said no one acted to help the couple.
"I saw an unknown person bring out a big knife and first hit him from behind on his [Avijit Roy] head and then on his shoulders. I shouted for help from the people but nobody came to save him; no one came. A lady was with him - she was his wife. She was also hit on the shoulder," said Kazi Shawkat Ara.
Bangladesh's The Daily Star also reported others witnessed the attack, but none came forward to help the couple or apprehend the assailants.
An unknown militant group, Ansar Bangla 7, claimed responsibility for the attack.
Roy "was the target because of his crime against Islam,'' the group tweeted.
According to Roy's family, in recent weeks Islamist radicals had repeatedly threatened him because of his blog, "Mukto-mona," or "Freemind," that promoted humanist and rationalist ideas and condemned religious extremism.
The Center for Inquiry, a U.S.-based nonprofit group, said it was "shocked and heartbroken" by the murder.
"Dr. Roy was a true ally, a courageous and eloquent defender of reason, science, and free expression, in a country where those values have been under heavy attack," the center said in a statement.
Reporters Without Borders rated Bangladesh 146th among 180 countries in a ranking of press freedom last year.
VOA's Bangla Service contributed to this report.