Police sources confirmed suspect Imran Ali, a neighbour of the seven-year-old victim, had confessed to his crime before an investigation team.
Forensic specialists confirmed that the DNA sample from accused Ali matches with the sample found from the girl's body, Geo News reported, citing its sources.
The accused's DNA also matches the samples taken from seven other minor girls who were abused and murdered earlier in the area, it said.
Ali was known to the girl's family and would also frequent her house, police sources said.
They said Ali had been taken into custody over two weeks ago but was let go on the victim family's plea that 'he could not be a culprit'.
Punjab government spokesman Malik Ahmad told PTI that Ali had confessed to his crime but it would be confirmed whether he is the culprit or not after a DNA test.
"Imran Ali's DNA test is underway and hopefully we will have the report later in the day," Ahmad said, adding the suspect has been arrested from Pakpatan district of Punjab.
After her abduction, a CCTV footage showed her walking with a stranger near Peerowala Road.
On January 9, her body was recovered from a heap of trash near the Shahbaz Khan Road. Autopsy report had confirmed rape.
Police have carried out DNA test of more than 1,000 suspects. The Supreme Court on last Sunday gave a 72-hour deadline to Inspector General of Police to arrest the culprit.
Violent protests gripped the Kasur city following the girl's murder that claimed two lives. The incident also stirred a national outcry demanding justice for her.
Last year, 4,139 incidents of child abuse took place in the province where 43 per cent of them were acquainted with perpetrators.
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