Pakistani police opened a hate speech investigation involving two Muslim clerics on Sunday after the killing of a university student over allegations he committed blasphemy.

The clerics are accused of attempting to disrupt the funeral of student Mashal Khan, who was beaten to death by fellow students after a dormitory debate was followed by accusations of blasphemy being spread across a university campus in the northern city of Maradan.

University officials had issued a public notification hours before the murder naming three students being investigated for “blasphemous activities”.

Sensitive topic

Blasphemy is an extremely sensitive topic in Muslim majority Pakistan, where penalties range from small fines to the death sentence, and dozens of people are on death row in the country's jails.

There have been at least 65 recorded cases of vigilante murders since 1990, according to figures from a Centre for Research and Security Studies report and local media.

In a statement, Prime Minister Nawaz Sharif said he was “shocked and saddened by the senseless display of mob justice that resulted in the murder of a young student, Mashal Khan, at Wali Khan University”. The government has been vocal about blasphemy in recent months, with Sharif issuing an order in March for the removal of content deemed blasphemous online and threatening “strict punishment” for those violating the law.

Mardan police chief Alam Shinwari said 20 people had been identified as culpable in the killing.