Eight Pakistanis involved in the mob lynching of a fellow university student over his liberal views were charged with murder and terrorism on Saturday, court officials said, as condemnation grew.
Mashal Khan, a journalism student, was stripped, beaten, shot, and thrown from the second floor of his hostel at the Abdul Wali Khan university in the conservative northwestern town of Mardan on Thursday by a large mob.
So far a total of 12 people have been arrested over the incident and police are hunting for more suspects.
"Eight students were presented before an anti-terrorism court in Mardan over murder and challenging the writ of the state," public prosecutor Rafiullah Khan told AFP.
Prime Minister Nawaz Sharif said Saturday that he was "shocked and saddened", his first statement on Thursday's killing.
"Let it be known to the perpetrators of this act that the state shall not tolerate citizens taking the law in their own hands," Sharif said.
"The nation should stand united to condemn this crime and to promote tolerance and rule of law in society," he added.
Mushtaq Ghani, Information Minister of northwestern Khyber Pakhtunkhwa province, said the government had also requested Peshawar High Court to conduct a judicial probe into the incident.
Graphic video footage from the crime scene showed dozens of men outside the hostel kicking and hurling projectiles at a body sprawled on the ground.
Rights activists and civil society organisations held small protests in several Pakistani cities Saturday condemning the murder, and the UN in Pakistan released a statement.
"We urge the authorities to take firm action and bring the perpetuators to speedy justice," said Neil Buhne, United Nations resident coordinator in Pakistan.
"Pakistan has strong legal institutions and it is unacceptable for anyone to take the law into their own hands," he added.
The independent Human Rights Commission of Pakistan (HRCP) has urged that all those involved in the lynching be brought to justice.
"The state?s abject failure to protect Mashal Khan?s right to life has created great panic and horror among students and academia. Unless all those who played any part in Mashal?s brutal murder are brought to justice, such barbarity will only spread," it said.
However, at Khan's funeral Friday a local mosque Imam who was also Khan's primary school teacher, refused to lead the prayer, Mashal's father Iqbal Shayir told AFP.
Shayir said he hoped his son's murder would "evoke realisation among people that killing an innocent is a sin".
Students had previously complained to university authorities about Khan's alleged secular and liberal views and Khan had been in a heated debate during a class the day he was killed.
Blasphemy is a hugely sensitive charge in conservative Muslim Pakistan, and can carry the death penalty. Even unproven allegations can cause mob lynchings and violence.
At least 65 people have been murdered by vigilantes over blasphemy allegations since 1990.