The incident reportedly occurred in the posh 13-D block of the city's Gulshan-e-Iqbal neighbourhood.
The FIR of the incident has been registered under Sections 302, 324, 334, and 337-A (i) of the Pakistan Penal Code.
According to the report, the woman, Shirin Asad was taken into custody after the death of the young boy.
The complainant, Qabool Manthar Ali, a resident of Tharparkar district, said that the suspect informed the victim's younger brother that he fell from a rickshaw some 15 days ago.
She claimed that the boy then slipped in the bathroom on Feb 8, and was rushed to a hospital where he breathed his last.
Besides the victim, two other boys, aged 13 and 16, had been working at the house for nearly a year.
Following the burial, when the victim's father inquired his sons about what actually happened, his 16-year-old son said the accused used to beat him and his now deceased brother.
The FIR went on to quote the boy as saying that the woman would beat the deceased with “heated tongs” and that “he had not fallen from a rickshaw”.
She had hit him in the head with pliers, which caused his death. He also said, “My brother had not fallen in the washroom.”
The boy then also stated that the accused pulled out his nails “with pliers”. The FIR also quoted the father as saying that he had witnessed “significant marks of torture” on his 13-year-old son.
“My plea is that Shirin Asad has tortured and killed my son and tortured another son,” the complainant maintained.
The father of the boys further revealed that he was told the boy was fine when he called him two days prior to his death.
Speaking about the condition of the other two boys, he said the 13-year-old was currently in a hospital due to the 'torture inflicted on him' while the eldest had "lost his senses".
The complainant claimed he was told by the house owner to not take legal action following the incident.