The policemen on the Dhaka University campus did not act to save Bangladesh-born blogger-writer Avijit Roy but simply looked on while he was being killed, his widow Rafida Ahmed Banna said .

“While Avijit and I were being ruthlessly attacked, the local police stood close by but did not act,” Banna, who survived the February 26 attack, said on her Facebook account.

“Now, we demand that the Bangladeshi government do everything in its power to bring the murderers to justice.”

The couple, who had arrived in Dhaka from the US a few days before the incident, were returning from the Amar Ekushey Book Fair when they were attacked by machete-wielding assailants on the university campus, bdnews24.com reported.

Few hours after the attack, Roy died at the Dhaka Medical College and Hospital due to the deep gashes on his head. Banna suffered severe head wounds and one of her thumbs was sliced off.

Roy, a bio-engineer, had angered fundamentalists and received repeated death threats for writing against religious fanaticism.

Banna, a US citizen, is now in the US after the state department arranged her return.

She had earlier told her father-in-law, renowned professor Ajay Roy, that she remembers the attackers’ faces and will be able to identify them.

According to her, there were at least five of them, all around 25 years of age. “They were in jeans and T-shirts. None had beards,” the professor said.

Roy never believed that an attack so heinous could take place on the campus, reputed to be a space for progressive movements and the place where he grew up, Banna wrote.

The detective branch has been investigating the murder with assistance from the FBI.

On March 3, the Rapid Action Battalion (RAB) arrested “fundamentalist blogger” Farabi Shafiur Rahman, a prime suspect.

Detectives said they have been trying to find out if the attack was carried out by his followers or Farabi himself.

He was earlier arrested for inciting attacks on bloggers on social media after blogger Ahmed Rajib Haider was hacked to death in 2013.