The parents of eight girls who had been raped and murdered in Kasur since 2015 appeared before the Supreme Court on Sunday and pleaded for justice.

"Give us justice," the parents ─ including those of six-year-old Zainab whose body was found in a trash heap on January 9 ─ pleaded before a three-member bench of the apex court.

The bench, headed by Chief Justice of Pakistan Mian Saqib Nisar, was hearing a suo motu case on the grisly rape and murder of the six-year-old that shocked the nation this month.

Zainab's uncle was present in the courtroom for the hearing, which was conducted at the SC's Lahore registry.

During the hearing, the bench expressed its dissatisfaction over the progress of the investigation into Zainab's murder.

"An unspeakable crime has been committed against an innocent girl," the bench remarked.

Muhammad Idrees, the regional police officer of Multan and head of the joint investigation team probing the case, submitted to the court a report on the investigations.

He said that Zainab's case is the latest in eight similar incidents of assault and murder since 2015.

The bench remarked that if the police had taken the matter seriously in 2015, eight girls could have been saved.

When the RPO told the court that DNA tests of 800 suspects have been conducted, the bench remarked that the police is pursuing a one-track investigation and must widen the scope of the probe beyond simply using DNA testing to track down the culprits.

"The DNA tests of 21 million people will have to be conducted if the investigations continue in this way," the bench said.

The chief justice told Zainab's family that they should inform the court of any complaints they may have.

"The JIT is doing satisfactory work," the family members responded.

"We pray that the team is successful [in it's probe]," they added.

The bench summoned the JIT and other parties in the case to appear in the court chambers for the next hearing.

RPO recounts events of Zainab's 'disappearance'

During the hearing, RPO Idrees recounted the events of January 4, the day that Zainab went missing in Kasur.

He said that at 7pm that day, Zainab left her house to go to her aunt's house ─ located at a distance of 300 kilometres ─ for Quran lessons.

According to the RPO, Zainab's brother, Usman, would normally accompany her to their aunt's house but did not do so on January 4.

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He added that when Zainab did not return home, her family began searching for her and informed the police at 9:30pm.

Zainab's body was recovered from a trash heap on Jan 9. The six-year-old's autopsy confirmed that she was strangled to death. It suggested that she had been raped before being killed.

He said that the culprit behind the seven cases of assault and murder of minor girls that preceded Zainab's is also responsible for this latest case.

He added that all incidents have taken place within the jurisdiction of three police stations, with the first two incidents having taken place in the remit of the Saddar Division police station.

"So many incidents have taken place, what was the police doing?" the court questioned.

"The incidents took place repeatedly in the remit of two police stations and no one conducted an inquiry," the chief justice observed.

No major headway has been made in the case since Zainab's body was found, despite the Counter-Terrorism Department, Intelligence Bureau, Special Branch and Punjab Forensic Science Agency each being tasked with investigating the case.

Kainat's medical treatment

During today's hearing, the court inquired after the medical treatment being administered to six-year-old Kainat Batool, who went missing in Kasur in November 2017.

After an exhaustive search, Kainat was found alive in a trash heap and admitted to Lahore's Children's Hospital for treatment where doctors said that no evidence of sexual assault had been found on her body. However, Kainat's family denied this account, saying there were torture marks on the child's body.

A medical superintendent from the hospital, appearing before the bench today, recalled that Kainat had been admitted on Nov 13 last year and underwent treatment there for a month.

The chief justice asked the medical superintendent to inform the court about the possible treatments that could be provided to the child. He added that if required, Kainat should be sent abroad for treatment.

The medical superintendent told the court that a board meeting is scheduled to be held at the hospital tomorrow and a plan for Kainat's treatment will be formulated then.