Kasur, Pakistan (CNN) Aasia Bibi last saw her eight-year-old daughter Laiba as she waved her off on her way to a Quran class in July 2017. She did not return for dinner.

That night, when Aasia heard a girl had been found dead, she felt her legs weaken and her body convulse.

"I was heading towards where they said they'd found the body. I couldn't walk, I was praying to God, saying, 'please, please, please don't let it be my daughter,'" she told CNN.

It was.

Laiba was just eight years old when she went missing in July 2017 after being abducted by a suspected serial killer.

Laiba had been raped and murdered. And she wasn't the only one.

On Tuesday, authorities in the Pakistani city of Kasur in eastern Punjab province announced they'd arrested a 24-year-old man, named only as Imran , who is accused of attacking and raping eight girls under the age of 11.

"The first phase of our investigation is now over. We have arrested this horrific creature," Punjab Chief Minister Shehbaz Sharif said at a press conference Tuesday.

The alleged killer's first victim was found dead in Kasur two years ago. The last was seven-year-old Zainab Ansari whose body was found dumped on a garbage heap, 100 meters from her home in the city center earlier this month.

Pakistani students light candles during a protest rally to condemn the rape and killing of Zainab Ansari.

Zainab's disappearance on January 4 led to a frantic search of the city by police and members of the public.

The young girl's body was found on January 9, five days after she disappeared. A post-mortem report said she had been sexually abused and strangled.

Zainab's death amplified the cries of desperate parents for police to catch a killer they feared was preying on children.

Television screens played and replayed closed-circuit television video showing a girl identified as Zainab being led away, hand in hand with a man police said could be her killer.

Angry locals demanded answers; violent riots erupted and two protesters died

Amid the outcry, Punjab Chief Minister Sharif ordered police to arrest the girl's killer or killers within 24 hours, and offered a 10 million Pakistani rupee bounty (over $90,000) for anyone who helped find those responsible.

that found on several other suspected victims who were apparently abducted within a four- to five-kilometer (two- to three-mile) radius area of the city. On January 15, Punjab government spokesman Malik Muhammad Ahmad Khan told CNN that DNA recovered from Zainab's body matchedthat found on several other suspected victims who were apparently abducted within a four- to five-kilometer (two- to three-mile) radius area of the city.

He said authorities had discovered a DNA link after the fourth attack. The killer struck again a number of times.

'The entire neighborhood is terrified'

Zainab's father, Muhammad Amin Ansari, says if the previous attacks had been investigated properly then the person who killed his daughter could have been stopped.

"If, at that time, they had found the killers after what had happened to those girls -- if there had been a proper investigation -- then maybe we wouldn't have to see what's happening right now," he said.

As Zainab's father spoke, her mother, Nusrat Ansari, stared down at the floor, her face wrapped in a thick blue dupatta.

Her daughter was "like an angel," she said, her voice breaking as she described the moment she heard that Zainab's body had been found. "It was as if the floor had fallen from underneath my feet," she said.

The parents of Zainab Ansari -- Muhammad Amin Ansari, 48, and Nusrat Amin, 45 -- hold their daughter's school uniform, jacket and Barbie schoolbag.

Amin said after Zainab disappeared her friends and neighbors had become paralyzed with fear for their own daughters.

"The entire neighborhood is (so) terrified that even mothers don't want to be alone at home with their kids without their husbands," she said. "If our daughters are not secure, then we ourselves are not secure."

Khan, the spokesman for the Punjab provincial government, conceded that police did not investigate the earlier deaths as thoroughly as Zainab's.

He said he had "no reason to deny" accusations by the parents the police should have acted sooner. "The only thing which I have to do is to restore the trust of those parents. I can feel their pain. We are doing our level best," he said.

'We were never given any warning'

Kainat's father Ahsanullah Elahi stands outside the Lahore Children's Hospital where she's being fed through a tube.

The parents of six-year-old Kainat feel that pain every day as they sit beside her hospital bed, praying for signs she's still with them.

"She doesn't recognize anyone," said her father, Ahsanullah Elahi.

Last summer, Kainat went to buy yogurt from a shop a few streets away from their home in Kasur, said Elahi. She was attacked and left for dead.

Her family said they were never warned that police suspected a serial killer was targeting children in Kasur.

"We were never given any warning," Elahi said. "We didn't know anything."

Kainat now has brain damage, is unable to speak and is being fed through a tube, doctors at the Children's Hospital in Lahore told CNN.

"I can't tell you how I feel. Whenever I look at her, I just feel sick with worry," Elahi said. "I'm sending out a warning to all the parents of Pakistan that they must protect their children."

The city of Kasur, Pakistan. Residents feel police did not do enough to catch a serial killer.

Scarred by sex abuse scandal

This is not the first time parents in Kasur have spoken of fears for their children's safety, and authorities' apparent inability to protect them.

In 2015, a child sex abuse scandal engulfed the village of Hussain Khan Wala, a half-hour drive outside the city in the wider Kasur district.

Then, more than a dozen men were together accused of abusing scores of children. They were said to have filmed the abuse and then blackmailed the children, threatening to expose the clips . The alleged abuse, thought to date back to at least 2009, was uncovered in 2015 and a number of suspects arrested. Two men were charged and later sentenced to life in prison.

At the time, angry locals accused police of attempting to cover up the abuse.

Three years later, Khan, the Punjab government spokesman, told CNN the media exaggerated the allegations.

"Once we investigated it, facts were very, very much different from what was reported in the media. First of all, the media reported it was 282 cases. When it was investigated by all means, on all aspects, the number was reduced to 10," Khan said.

One of the abused children is now 18 and carries the shame of the crime committed against him. He said he was eight years old when a man from the village offered him a ride on his motorbike.

"We reached a house where there were other men as well," he remembers. "They grabbed me and beat me up... I was sodomized. One of the men made a video of what was happening. Then they told me that unless I paid them money they would make the video public."

Child protection advocates say a large number of children were abused but only about 30 cases were registered with the police. Victims and activists are demanding more prosecutions.

"I feel like if we didn't get justice then those girls won't get justice either," the abused teenager said. "All these beasts are in the same boat ... If, since 2015, we have been pushed around and not received any justice, then (Zainab's) father will also be pushed around ... The state won't get him justice."

'I only worked for my girls'

Laiba's mother Aasia Bibi, 35, holds a photo of her daughters who she hoped would one day be there to care for her.

Laiba's mother, Aasia, sits on a step, wrapped in a black shawl, and talks about how she assumed she'd grow old with her two daughters to take care of her.

She's a single mother who works as a housekeeper to support her family.

"I only worked for my girls, earned for them," she said. "I wanted to educate my girls so that they could grow up and become my support ... I cleaned other people's filth, their clothes, their dishes for my children -- and what did I get?"

In the aftermath of Zainab's death, authorities in Punjab have created a commission for child protection. A document submitted to the High Court in Lahore this month shows the scale of the challenge they face.

Police reported 137 cases of girls under 10 being raped in Punjab last year, and 515 of boys under 10 being sodomized. A further 15 girls were raped and then murdered, and 10 boys sodomized and killed.

Zainab's father Muhammad says it's too late for Zainab, but he can only hope her death helps to protect others.

"I pray to Allah that, because of Zainab, in the future our daughters, all the sons and daughters of mothers, are kept safe."