Eight-year-old Zainab Ansari went missing last week while heading to a nearby home for Quranic studies. DNA samples have also been taken from 90 possible suspects.A post-mortem report suggested that Zainab had been brutally assaulted.
The girl was on her way to a Quran recital when a man approached her, grabbed her by the hand and led her away.
Zainab's father, Ameen Ansari, told the BBC that he did not agree with the violence of protesters, but understood the anger at police."If the police had done their jobs properly then they would have found her as soon as they got hold of the CCTV", he said.
"This is not just the murder of a small girl".
He said police had been exploiting the cases to collect money from a large number of people after arresting them for suspicion.
Kiran's protest struck a chord with many from across the globe and she later explained why she made a decision to bring her own daughter to the news show.
Zainab was taken from near her home in Kasur on January 4 while her parents were in Saudi Arabia on a pilgrimage, CNN's Pakistani affiliate Geo News reported.
On Tuesday, a police constable deputed to trace the girl recovered her body from a trash heap.
A division bench of the Lahore High Court on Friday ordered the Punjab inspector general of police (IGP) to arrest without fail the killer of innocent girl Zainab within 36 hours.
It is the 12th such murder in the town of Kasur in a year, and has raised concern that a serial killer may be on the loose.
"(Sharif) has announced Rs 10 million ($90,000) for anyone giving information about the kidnapper", Punjab government spokesman Malik Muhammad Ahmad Khan told Reuters.
Kasur made worldwide headlines in 2015 when a gang of paedophiles running a child sex ring was busted, Dawn reported.
Two people were killed by gunshot wounds as enraged protesters armed with sticks and stones attempted to storm the deputy commissioner's office and clashed with police. The gang had allegedly abducted and sexually assaulted at least 280 children in the area, had blackmailed the families of the victims since 2009, and even sold video clips and images of the assault online.
In March 2016, Pakistan passed a law against sexual abuse of minors and child pornography, making the crimes punishable by up to seven years in prison.