ISLAMABAD - The father of a university student who was killed by a mob over blasphemy accusations told Pakistan’s top court Wednesday that his two daughters have received death threats and should be transferred from schools in their hometown.

Mobile phone video of Mashal Khan’s brutal slaying April 13 at Abdul Wali Khan University Mardan went viral, shocking the public and sparking condemnation, including from prominent clerics. It has cast a sharp focus on Pakistan’s blasphemy laws. An investigation showed Khan had not made online posts that had been attributed to him.

The journalism student’s father, Muhamamd Iqbal Khan, addressed reporters after attending a Supreme Court hearing on the case in the capital, Islamabad.

“Mashal’s sisters cannot continue their education due to threats to their lives,” he said. “They must be transferred to Islamabad from their hometown of Sawabi.”

Iqbal Khan also said the trial of suspects in his son’s killing should be transferred to Islamabad from Mardan because of security issues and local administration attempts to influence the case’s outcome. The top prosecutor of Khyber Pakhtunkhwa province, Advocate General Waqar Khan, told the court that 53 of the 57 suspects have been arrested.

Ambulance workers load the body of Mashal Khan int The body of Mashal Khan is seen loaded into an ambulance after a mob beat him to death at his university campus in Mardan, Pakistan, April 13, 2017. The body of Mashal Khan is seen loaded into an ambulance after a mob beat him to death at his university campus in Mardan, Pakistan, April 13, 2017.

The Mardan university should be reopened, with more security, so students can resume their education, Iqbal Khan said.

Critics claim the government’s push to make blasphemy laws even tighter is aimed at quashing dissent and intimidating opponents. Other violent attacks have been attributed to blasphemy allegations.

Human Rights Watch on Wednesday urged Pakistan to end excessive state monitoring of internet activity, prosecute those committing violence based on internet blasphemy allegations, and commit to upholding free expression for all.

The government-run Pakistan Telecommunication Authority sent a text message to millions of citizens a week ago, warning against sharing “blasphemous” content on social media and asking them to report such content.

In addition, Interior Minister Chaudhry Nisar Ali Khan last week ordered the Federal Investigating Agency to take immediate action against “all those dishonoring the Pakistan Army through social media.”